I'm going to ramble about a game 99.9998% of the gaming population has never even heard of, nevermind will ever play. Even among codexers, I'd be surprised if 1/100 have played or will ever play this game.
It's a MUD, and it's run by fucking assholes, and parts of it are disgustingly bad, but that won't stop me from gushing about what the game does right. It's called Hellmoo, but really, the engine is called HellCore, so I'll just refer to it as that, there are other servers... if they could ever just get off the ground.
In hellcore, movement is stratified and it makes so much sense. If you took hellcore's mechanics and put it to a AAA engine we'd be singing praises to Roguey because the end of the world would be here.
Movement has risks and rewards, more or less is the gist of my blathering - it's why games today suck shit. There are few risks and bland rewards. Everything is +10% to X, oh no you died better reload that checkpoint mate!
Anyway, here's what it does right:
Fall damage is potent. This means, you can't just jump down 30 ft and giggle like a schoolgirl; falling is deadly and it means you need to be careful where you step. This gives weight to your travel options.
On one hand, the game offers air travel. You can:
1) hire an air taxi (gyrocopter); this is public transportation and it has limited travel destinations - but there are airports all over the world map, so it's pretty handy. You need to wait for a taxi to arrive, so it's not that convenient, and it's expensive. It's also a little dangerous - it's public transport, so another player could be riding in it and kill you if they're a dick (some assholes carry a bunch of explosives on them and suicide bomb taxis for the fun of it). That's pretty rare though. It's safe, because an NPC is driving it, so you won't accidentally run out of gas and plummet to your death or something stupid like that, and it's available to anyone at any level. It's limited, but it allows you to go wherever you want, as soon as you start the game. Taxis potentially let people play the game however they want from the onset of the game. They can stay in the starter areas or right away fly somewhere dangerous, at a farmable monetary cost.
2) buy/build an air vehicle (gyrocopter/zeppelin/freight ships); this option is awesome - you can fly wherever you want, but only to an extent. Normal areas are safe for air traffic, but dangerous high level areas are guarded by sky pirates or worse, anti-aircraft guns on the ground. You can only bypass those by acquiring stealth radio frequencies to fly through them, or by destroying them... or by trying to run past them (pretty much suicide or will do expensive damage to your ship). If your ship is destroyed, not only do you plummet to your death, but any items you were carrying will be strewn all over the area below you - this makes air travel fast, freeing, but also at a great cost. You need to fly careful, you need to purchase fuel and not try to fly on empty, and you need to be aware of what obstacles can prevent you from flying somewhere ahead of time. Zeppelins are also house-ships, so you also have the option of relocating wherever you want in the world, potentially. This option is only for players who have accumulated wealth and power and knowledge about the game, but it's rewarding because it takes time to get here and lets you do a lot of cool stuff once you've mastered parts of the game. The goal of reaching this stage in the game is what drives many players to keep exploring, to find more parts to build "that ship" or that thing that lets them advance closer to this stage.
3) Fucking fly. In Hellcore, players advance their characters by picking certain "mutation powers" - one of which lets you just fly yourself. This means you don't need to buy and maintain an expensive air vehicle and you're not quite as restricted in where you can fly (a helipad isn't required to land somewhere). This means you can take off to escape enemy players or mosnters you can't handle, without having to "lift off" or run back to a ship. It also means you're much harder to kill in the air - if your ship blows up, you can always bail out and fly around instead of plummetting to your death (you can even potentially become a sky pirate yourself, barging into people's idle air vehicles in the sky if you're skilled enough). On the other hand, flying with your fleshy body is pretty dangerous. It's super cold in the air, so you need to bundle up or you'll freeze to death (this restricts your armor options). There are also airborne enemies that don't attack ships but attack flying players... uhh chupacabras. Pretty obnoxious. This kind of mobility is more personal and lets people who really like exploring in the sky do so.
On the other hand, you have land travel:
1) Walking. Everyone can walk. The problem with walking is the game has a survival system - you need food and drink. Walking makes your thirsty, so you need to carry water around. Water is heavy. Finding fresh water in a dangerous toxic place isn't usually easy. Walking is probably the "safest" travelling option, but it's also hugely limited and slow. Also, temperature matters. If you walk somewhere freezing you might actually freeze to death if you don't prepare before hand. If you walk somewhere super hot, you can die from heat exhaustion. You can't walk around mountains trivally like in Skyrim...
2) Climbing. Yes, in Hellcore, climbing actually is a skill you need to level up. If you try to climb a mountain with no concept of grappling rocks you will fall. Falling from more than 10 ft is going to do impact damage to your character. Falling more than 50 ft is probably going to kill you. Falling can falling can cripple you. If you fall you can and often do break your legs or arms. One of the most crazy fun times I had was climbing down a horrible mountain with one broken arm. Not only that, but I was a Vampire, meaning, I needed to get off the fucking mountain before sunrise or I was toast. I barely made it and it was an adventure.
Some people would cite some of this as "tedium" but the whole point of a good RPG is to go on an adventure. The climbing mechanic - the fact you need to scale mountains or cliffs or super tall ladders and ropes - is integral. It adds height to travelling. There's no "walking alongside the side of a mountain" - you actually need to climb it. Good exploration is more than "you can climb that mountain" it's more like, "Climbing that mountain is tough, but if you do it... You'll have an adventure." In Skyrim, you will spend an hour or so glitching around a mountain only to realize you didn't really run into anything interesting, lol. At the top of most of the dangerous climbs in Hellcore, is at least something novel - if not some well-deserved experience or a new mutation or rare item used in crafting or something...
And you can also bypass climbing, one mutation lets you "leap" high, letting you skip this mechanic if you hate it. You can also mutate your character to significantly reduce falling damage, at a cost of becoming heavy and bulky (less carry weight).
3) Ground vehicles. This is of lesser use, but still improves the tedium of walking. Ground vehicles can get you in "car accidents" and cost some money or need to be crafted... and they take fuel... But they offer a quick alternative to foot travel.
4) Clairvoyance. This is definitely one of my favorite mechanics. As a clairvoyant, you can astrally project yourself anywhere. You can't "physically" go everywhere, but you can move through doors like a ghost, see horribly dangerous places (or just locked places that need keys you don't know how to get yet) and obstacles from super far away. As long as it's not coated in foil, you can really explore anywhere. It's a great mechanic, because if you want to walk to that place, it may have changed since you last astrally projected so there's still risk (and you need to lie down to project, which makes you vulnerable too). It's a great trade-off of letting you quickly determine if it's a waste of time to do adventure A, because yeah, there's nothing on the top of that mountain worth getting right now. Of course, you have to give up the option of flight or teleportation to obtain this power - so it's really letting players decide how they want to operate in a mobile sense - do you want flight on demand, or knowledge about areas you want to visit on demand?
5) Blink. Basically, teleportation. You can memorize a location and then travel back to it whenever you want. This is extremely powerful, as it allows for quick escapes - but it can also backfire. It has the biggest "investment" - you need to have a specially focused character to do this (kind of like a mage), if you fuck up and fail your roll, you can gib yourself with a botched teleport, or you can teleport somewhere (horribly) unexpeceted. Like clairvoyance and flight, it's mutually exclusive.
6) Other shit, I mean, vampires can turn into mist, there's a subterranean race mutation that lets you use sewer systems for speedy movment, and you can set up remote camera systems and tether them to your wristpad to monitor areas you want to control (letting you be in multiple places at once, essentially).
Did I mention there's also water travel?
Swimming is also of lesser note. Boats are nice places to store your loot, since they're mobile and hard for other players to locate on the vast "sea".
All in all, what I think I'm trying to describe here, is a multi-faceted system which lets players choose what kind of risks they want to take when they go on an adventure. They can skip tedium by taking risks (risks that involve dying and/or losing the items you're carrying) or by paying fines (fuel/taxi cost) or by being "forced" (you probably enjoy it anyway) to build a certain way to get advanced movement powers. But most of all, what makes it all work is each method promotes an adventure. No method is 100% safe or 100% "free", each presenting its own obstacle. And what this accomplishes is that each time you want to go somewhere, there's a good chance you'll actaully get there in a reasonable amount of time (or just survive the journey at all)... and there's also a pretty good chance you'll be thrown into a new experience - some monster you didn't see coming, or maybe you broke your arm on the top of the tallest mountain and now you're going to starve up there or die... It's just great. Clairvoyance is especially fun, many times I recall saying, "Fuck, so glad I didn't try walking into that room, I would have been murdered instantly."
The problem with Skyrim is that walking vs fast travel is pretty much the same thing. Only, walking just eats up your day. The main issue with Skyrim is... aside for some preplaced static one-time events at each location, there's nothing to experience. Nothing is dynamic. There's nothing even that dangerous. Nothing could possibly excite you. Hellcore is a MUD, so it's helped by the random events generated by players, but even there, there's so much dangerous stuff that can happen while travelling -- that it's exciting. It's also exciting because travelling is rewarding - you find shit and you take it back home. In Skyrim, was there any one item you were glad you "found" and made some adventure "worthwhile"? Fuck no, you'd go back to some questgiver and sigh because the tedium was over and you did that thing not that the thing itself was at all worthwihle.
So essentially, yeah, it all boils down to Skyrim being a bad fucking game. Nothing special. Big surprise.