First of all, I don't think "realism" matters one bit. It's really all about gameplay, especially for a game like KoTC. If the game was all about atmosphere and stuff with less focus on the battle system and only few battles... like the Realms of Arkania games eg., then, maybe it would be more important.
All the first RPGs I played were MP-based, and I still like the slot-based (D&D) system. What I really hate though is the memorization part of it. But this is, fortunately, not in KoTC (and will hopefully stay like this

).
I don't get what you all don't like about the Wizardry 8 spell system. For me, it's one of the best ever made. About that leveling skills thing, you really don't need to do that. It's not required at all, I didn't level a single spell or skill the first time I played it, and it wasn't unbalanced or anything. Even if I play it nowadays, the only additional "skill leveling" I do is healing my party members with weak casters after a battle instead of resting etc.
VentilatorOfDoom wrote:Of course Wiz8 does additionally suffer from stupid design desicions like making the majority of spells useless
I'm
really suprised to read that. Seriously.

Which spells are useless in your opinion? I just checked the whole spell list and I used most of them. Some of the spells, like shadow hound (wakes you before enemies are attacking when resting), I used only rarely, but that was because I was too lazy.

Most of the other spells I didn't use aren't useless per se either, because I remember enemies (effectively) casting them on me - I guess I just didn't like them.
It's uncommon that mental spells (or spells that inflict negative conditions) where the most effective at the beginning whereas damage dealing spells became a lot stronger at the end - but I liked it.
But maybe which magic system you enjoy depends on how you play your mage. I'm really penny-wise when it comes to spell lots/MP. In most RPG's, I mostly cast spells when really necessary. I often have the feeling I wasted something when I use spells although I could have won the battle without it. It was different in Wizardry 8, because you improve your casting skills when casting.
Actually the system is very similar to the D&D system, just a lot simpler and easier to understand. Instead of D&D spell levels you have magic realms and instead of metamagic feats you adjust the power level of every spell when casting.