My favourite approach is certainly a mix between some frequent important handcrafted and handplaced battles and overall easier "random" encounters from tables of encounters (they're more or less handcrafted but occur randomly) ; it's what is used in the SSI Gold Box games.
I think it's even better than only handcrafted encounters like in Knights of the Chalice (which have an option to activate or deactive random encounter, but most of the time random encounters are not interesting here so let's admit it's deactivated).
I think this or these approaches are the right one if you want to make some short, compact game. I think Voidspire Tactics has less than 100 fights in the full game, all handcrafted and all different or so, which is great.
Note that in the above games, a lot of encounter can be deadly and you can save your game whenever you want.
That said I have no major problem with games like Elminage : Gothic or the Final Fantasy games where the ratio random encounter/"boss" battle is much higher but there's no tactical map and the duration of a fight is much lower. I understand that random encounters can be boring sometimes, but as long as they're not both long and easy they're OK to me.
If a fight is won in 3 clicks, 1 or 2 turns, 30 seconds?, using the good skills, a few MPs (and items) and having a character being poisoned or stunned (or killed in one turn), and that the enemies in the game are varied enough then small random encounters can be appropriate.
Each battle is not meant to require some wargaming level of strategy here, you only need to be prepared, perhaps also not to enter a zone you shouldn't already enter, to properly manage your resources and use one or two appropriate skills. In particuler if the dungeons have more to offer (good puzzles or traps) than a sequence of encounters, that can work, and you can spend more time designing the world, the dungeons, the monsters, skills, etc...
Now there's a major difference between Elminage : Gothic and Final Fantasy ; in the first one you can save everywhere but you can often face brutal encounters and die while in the second (like in a lot of classic JPRGs) it's the opposite. Not being able to save everywhere is fun, and it definitely reinforces the resource managment aspect. Now what is a little sad with the FFs at least from the PS ones and of many recent JPRGs using this approach is that they're often a little too easy, so you'll generally reach the end of the next dungeon on first try without having to particularly pay attention to your resources, while FF1 is better in that aspect because you often have to decide to get back to town not to lose your precious last earned XP and items. I think the real problem is there, it's not fundamentally that encounters are randomized.
Besides the Wizardry games mostly use the FF approach to saving but are harder and that's working fine.
Now regarding enemies which are visible on the map or not, it doesn't matter to me since most of the time I feel some compusilve need to run into every monster I see so it's just the same
. But to answer your question making enemies visible on a map and as a precise example on the world map is definitely a way to allow you to gain some time just avoiding them when you consider there's nothing to gain anymore from fighting them ; however in a dungeon it's a double-edged thing since being able to avoid monsters is not necessarily a good thing (that you need to manage to flee if you want to is part of the deal). Maybe the good approach, instead of making enemies both visible and easy to avoid, is to make easy encounters directly won like in Earthbound (well maybe enemies are easy to avoid, I can't remember, but you get the idea) or weak enemies flee before the battle like in Disciples of Steel.