I have played many versions of D&D including the basic, expert, etc... series, AD&D 1st ed, AD&D 2nd Ed, D&D 3.0, D&D 3.5. Many of these have been modified by things like Role aids, the Companions, Thieves Guild, Judge Guild, Arduin, and other 3rd party products.
I dislike the older editions for several reasons.
1. Racial level limits.
2. Wonky rules for multi-classing and dual classing.
3. No core skill sets (optional if you have the Oriental Adventuers, Wilderness Survival Guide and Dungeoneer's Survival Guide).
4. You mention "role playing", but how does that help pepople who don't necessarily like to role play and are there for the game? Well, it doesn't. At least with a skill section, they can make a skill roll and move on to the better things.
5. Dragons and demon lords were extremely weak in the 1st edition of the games. As were gods. Not saying that it'd be impossible to kill any of those things in 3rd ed, but they are much more powerful now.
6. No unified mechanic. Clerics have a nice turning table, combat is resolved on a funky combat matrix.
7. Too many varieities of saving throws.
8. Different experience point tables for the different classes.
9. Many of the classes have no unique factors among themselves outside of stats and equipment. A fighter's special abilities for example, include % strength, higher constitution bonus, and if you have Unearthed Arcana, Weapon Specialization.
I could go on, but for me, those are all things that make me glad to have 3.5. Then again, I like GURPS, Harp, Rolemaster, Rolemaster Standard System, and Fantasy Hero so the 'crunch' factor for me isn't an issue, it's a blessing.