Tl;dr good shit, had lots of fun from start to finish. While it's tempting to say that it can't really be compared directly to Conquistador, because the two are very different games (which they are), I'm p. sure it's fair to say that Viking's an objectively better game overall. I remember Conquistador getting boring from roughly around the midpoint, while Viking felt fun all the way through.
That said, it does some things much worse than Conquistador. The main stinker is probably the exploration/travelling, which has been so butchered that it might as well have been axed completely. The only point to the overland map is going from point A to point B, stopping at the closest camping spot to point B to remove starvation and whatever wounds anyone could have taken during whatever random "[x] falls under the ice!!" events. Oh, and I guess to trigger some of the camping events like Grimnir or butthurt britons leaving the party. Tbh it's just annoying and pointless in the end. And it gets even worse for sea travel, because I can't even tell if it's particularly faster than going by foot, and to make matters worse it doesn't let you camp/heal while on board, which is an absurd oversight considering how likely you're to run into "x and y get hurt" events,
especially that piece of shit random encounter with a jelling ship that always leaves two of your dudes severely/moderately wounded.
Another thing I was missing a lot compared to Conquistador were the "set up traps and hold out" moments. There is very little to no reason or occasion to use traps in Viking, which is half due to its being easy overall, and half because they are just regular consumable items to use, and I'm pretty sure it's not particularly worth spending actions on them that you could instead apply on clobbering the enemy dead. Especially since the AI tends to play things safe and stick to its part of the map. Also, the idea that you are setting traps
during the actual fight is just a tad too much for my sense of plausibility.
Character progression was another thing that I thought was meh. This is probably connected to the butchered camping, since you can just keep pumping combat abilities for half your dudes that you always use for battle, and camping abilities for the ones you don't, with very little choice/breadth to be had. The fact that you also get to make a few custom dudes before leaivng Denmark whom you can specialise from the start into camping imps is pretty ridiculous as well. At first I also thought the progression tier limitation by maximum skill points spent was weird, but then I read in Tigranes's revio that this was unlimited initially and made things completely broken, and I can certainly see how that could have been true - again, because half of your dudes just spec in combat, the other half in camping. Gear progression is mmmmeh as well, especially for armour, because weapons on the whole tend to be cool and varied - and then there's also the craftung which is completely ridiculous and which I consciously avoided so as to not become even more ridonkOP than normal.
And the final thing I really didn't like were the arbitrary power/prosper ratings, connected to arbitary homestead upgrades, arbitrarily governing endings. I was actually legit upset to find myself arbitrarily barred from initiating total brexit by the fact that I couldn't max the arbitrary power counter. Because everything about this is arbitrary, and none of it ever looks any important or meaningful until the game goes "Gotcha! Shoulda planned ur homestead more about power, lolololo!", and it's especially dumb that you can increase prosper with money, but not power - hello? Mercenaries are a thing? I'd also say it's even worse when you consider that so much verges on the pointless homestead in this regard, when Orkney feels much, much more like a tangible and significant/meaningful player HQ.
Now to proceed to things I liekd.
The combat I think is pretty serviceable and has a few cool bits. It might not be spectacular but it works, and I liked that the general combat abilities etc were kept reasonable and well-balanced, so they never felt like awesome buttons. Its biggest hindrance is probably that it's overall rather easy, but there are still a bunch of fights and setpieces that were very fun and kind of tricky. The church next to Perth that has like 15 dudes inside in close quarters definitely comes to mind. Others also include the fight against Skakki outside Caustantin's throne room, the barrow wights + angry mob in Skerninge, some wolf encounters, and definitely Aiblinn's rebels at Dun Phris - it might have been the coolest one in the game.
General campaign pacing is probably the game's strongest suit. The way you start in Denmark and do the smaller preparation errands, then you land in Scarborough which has an excellent feel of being a stranger in a strange land, then you go around doing stuff for the Anglos and Picts, and finally there's the big escalation, coming back home and... plot twist!!!! (with Rurik - which I didn't actually see coming, but which was neatly foreshadowed on reflection - in general the game does well with foreshadowing certain events and leading up to them).
The reactivity/C&C seem fairly stronk too. One of my favourite bits was getting the option to send many of the folks you meet to Orkney once you become the jarl, like the Roman larpers. The way the non-lethal toggle in wombat ties into this (and general quest design) is great as well, and the non-lethal toggle is something I've missed in RPGs since
forever. It's the ultimate response to situations when the player feels strongly about clobbering someone over the head, but not strongly enough to kill them, or when you feel like it'll be more profitable to spare someone and capture him than kill him outright. And the game very often acknowledges those possibilities - and obviously while it doesn't do so
always, because that would be absurd, it definitely manages do get it right for every time when it's very obviously needed. Also, obviously the C&C wouldn't matter much if it didn't have good quest design and set pieces to accompany it, and Viking is happy to oblige. The quest design might not be astounding (since the goals etc are pretty simple overall), but it presents you with some really cool events with multiple ways of resolving, and the way you should resolve them isn't always particularly obvious - by which I mean the choices you get are much less "moral" and much more pragmatic, which funnily enough makes it sorta similar to ELEX, which I've praised for the exact same thing. From the perspective of a playa playing a game, pragmaticism is a much more involved and practical layer of decision making than the petty moral dilemmas of pixel people. Still, one thing I found disappointing were the "big mystery!" quests like what happened to Urdad's expedition and Avalon. The former is the biggest "wait, that's it?" moment in the game, and the latter probably would have been just as bad if it hadn't given you one of the two most powerful waffen in the game.
Story/writing/historicity are great as well, albeit with some hiccups, like with some depictions of christianity, but eh that's mostly sperg territory. What I liked about the overall "story" (I mean it's sorta hard to say the game even has that much of a story because it's very low key and more like just a premise, but I think it's very much to its favour) was that while the action is focused on Britain and you spend most of your time there, the overarching importance of your status and clan in Skjern is always there, and the way the game ends with the post-Althing events is IMO very strong and a testament to the good ideas on which Viking is founded. I feel like any other stupid game out there would have either ended the moment you left Britain (cutscene of Althing and everyone being soooo happy!), or would have some strongpowerful importantsignificant muh deep narrative going on in Britain, or would have the Althing being settled by... trial by combat! Also, the way Skule's dudes keep pestering you all the time in Bwitain while he stays offscreen until the very end makes for good pacing as well. And getting to finally murder them is extremely satisfying - in general, Viking has many satisfying moments when you finally get to shank assholes who've been a thorn in your side for months.
Also, music. Music is universally great.