I think in the time I read this thread, 6 new posts showed up. Hot topic!
The last d20 campaign I ran pretty much turned me off to the game. It was a high level game (it ended at 15th level), and the combats were so exceedingly complex it wasn't even funny.
All the old arguments apply - templated monsters with multiple abilities, spells, strengths and weaknesses. Add in lots of magical effects, and annoying spells like Wall of Force (on both sides), invisible creatures, mirror image, blur, darkness, Prayer effects, and then in the middle of it all someone wants to charge and do a shield bash through multiple opponents to get to a BBEG and it's enough to make you want to pull your hair out.
And I can handle complexity, but we constantly got into gray areas that I had to adjudicate, and frankly I'm just not that good at that. Plus, my group was made up of people who were smarter than I was, so if they didn't like my ruling, they would debate the point until I conceded. My group had two PhDs, and a masters in it! I couldn't outsmart those folks no matter how hard I tried.
But D&D is a -very- specific kind of game. It's a game where, if you play it as written you've got situations that crop up like - can you dimension door into an anti-life shell? Does mirror image work against a half-orc with darkvision in the middle of a pitch-black dungeon? Does a daylight spell work against a vampir that you have trapped inside an Otiluke's resilient sphere?
I mean, jumping Jesus on a pogo stick - can it get *more* complicated?
I decided that my next game was going to be simple - with an emphasis on role-playing, not micromanagement, and roll-playing. I wanted a story-driven game, with personality and flavor, and history. Not, which PrC should I be planning for, and what spells work best in what situations kind of game. I also decided that d20 was not the game for me, since the kind of game I wanted to create pretty much can not be created with the ruleset that d20 presents. That's not to say that I don't like it, or that others should stop playing it. If people like playing Synnibar, by all means don't stop on my behalf. Play what makes you happy. I'm still shopping around for the system that I think closely matches my ideal. I've gotten HARP, and like what I've read thus far. I intend to get Grim Tales, and my DM (drife on here) informed me that the next campaign he's starting is going to be Harn, so I'll get exposed to that, and I'm excited.
The thing of it is, is this - d20 is a very specific *kind* of game. You can not, without altering the mechanic of the game remove some very basic concepts - all elves have the same modifiers, all clerics are built from the same template, fighters are good at combat, and wizards are not, and at the high levels of the game, it is assumed that you will have a deficit-breaking amount of magic items that are almost required to survive the typical kinds of powerful creatures that you are going to be facing. A 20th level D&D d20 game where the players only have a +1 weapon to their name are going to really struggle in a RAW kind of game. While it's not a requirement that they all have +5 whatevers, if they don't have at least several +3s or better, you've altered the core assumptions of the game, and the entire game only works *well* if you stay within those guidelines. Otherwise, CRs become disproportionate, and things could get really ugly. I don't like that.