ZyroMane: Boss fights are one of my least favorite things about video games. Especially when they have new mechanics the player has to learn. I love games with pushover bosses, like Doom, or the original Metroid. That being said, I did have fun overcoming the first boss in Legend of Grimrock II with my all rat party. It took three times, and a healing potion, to get everyone through it alive. Funny, that party is almost entirely "warriors." But I took an alchemist over a fighter.
It really depends on the game.
In many RPGs, particularly JRPGs, boss fights are often the only fights that last long enough for support magic to be useful. Or, for that matter, damage over time magic, assuming it works on bosses. There is, however, the common trend of bosses being immune to all status ailments; this is, for example, a problem in Final Fantasy 3 and 4.
I don't like bosses in platformers, like Mega Man games for example, as the platforming basically stops at that point until you manage to get past the boss. Basically, it's a bit too much of a change in gameplay here.
On the other hand, Celeste is one case of a platformer that doesn't stop the platfoming when the main boss fight (in a game with very few enemies; most deaths are from spikes or other obstacles) occurs. Celeste's boss fight works as follows:
* You enter the room, and there's the boss, in some spot in the room.
* You have to do some platforming to reach the boss.
* Once you get close enough to the boss, you hit them, the boss moves to another location in the room, and you get knocked back (and regain your dash).
* After a certain (small) number of hits, the boss escapes the room, destroying part of the wall (or floor) so that you can follow.
* The process then repeats in the next room. (Note that, in Celeste, each room is a checkpoint, even during the boss fight. You'll respawn at the start of the room when you die, and if you quit the game and reload, you'll start right in that room.)
It's really one of my favorite boss fights.
By the way, I've actually found the final boss of Metroid to be rather difficult, and I don't think I've beaten it. The same is true with the corresponding boss in Metroid: Zero Mission on Hard mode. On the other hand, the Super Metroid version of the boss isn't that hard, provided you have enough health to survive a certain unavoidable attack (if you do not, you might as well reset the game, and I hope you didn't save at the last save point without enough e-tanks.)
As for your Legend of Grimrock 2 party, I don't know how the balance is. Some games favor physical attacks (I think Wizardry 8 is such a game), while others favor magic (see Saviors of Sapphire Wings, where Wizard/Healers using the Healer's offensive spells can do huge amounts of damage, for an example, or Final Fantasy 6).