I like games with a random magic element... and I know that at least one of the players in my current group (my brother) is a huge fan of it as well. In our last 3.5E game, he played a wild mage... in our Iron heroes game, he played the arcanist (and loved triggering the negative effects)... and if we were playing Warhammer, he'd be gunning for a wizard just for the Curse of Tzeentch (or whatever it's called).
Triggering negative effects with your magic is great, because it puts a limiting factor on your spells. Dark Sun is great for this, because whenever you cast, you have to think creatively. Sure, it might be useful to cast Charm Person on that merchant... but if I do, plants nearby are going to rot, and I could get lynched. And yeah, I could cast Sleep, but where am I going to get more Rose Petal components?
A while ago (two years, maybe?) I played a Wu Jen caster, and he was probably my favourite 3E spellcaster, simply because of his Taboos. His magical drawbacks - rather than his strengths - were what made him a fun character to play.
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On the "character death" side of things... yeah, it can kind of suck when a character dies, but it happens. And when it does happen, I sort of embrace it, because it makes me realize that my actions can have serious drawbacks. My players generally accept character death, and roll with it. If I killed off one of our characters (all of which are at least six months in), I think the players would grimace and make up a new one... and then gloriously share tales forever after.
(Seriously... since my 4e campaign began, I've killed off around six PCs, and only two of those were raised from the dead... and yet those characters' deaths are fondly remembered).