I can agree with you here except... the Priest class was, while flavourful, poorly represented in the core books. While the Druid class was a decent example, it wasn't a good enough example to explain how it worked and the scant information presented was easy to abuse. I think the simplicity of some elements of 2e made it more complicated than it needed. I also think that 1e was more complicated than you remember by the core rules. The initiative system was complex and magic was complicated as well (this extends to 2e as well) with segments etc. forcing the DM to remember when the wizard's spell will go off. Further the grappling system was barely workable because of its complexity (but a far cry better than 2e's simpler system... of random charts!). Psionics were also very complex in 1e and 2e. The randomness of the rules really overcomplicated the game in many ways.
I think calling 3e complex though is a misnomer. I'd say a more applicable word is intricate. 3e is a very intricate and detailed system (3.5 for some reason more so than 3e itself while also being the same system...

) and sometimes that intricacy is a detriment to the game.
I have 4e, haven't played it yet, but the game seems a lot less intricate, but more intricate than AD&D1 or 2 and Basic, what with the powers etc. and I think that 3e, when played with D&D in mind as opposed to the "gee whiz, kewl powerz, roxxors, monster character, powergamerz" mentality is the best edition of the game that I have played. I prefer to run old school games, if you want to multi-class you need to be trained by an NPC and/or have a 16+ in the prime attribute of the class in question (Sorceror's don't need to be trained, they just need to have a 16+ charisma plus MAYBE some other elements I decide upon). Even Prestige classes need to be trained so if you plan to take one, you need to be trained by one and need to find him via the Guild. I really dislike a LOT of 3e builds. LOL.
That said, I hope to try 4e when I can get a group together here locally. I just moved in the last few months and can't find anybody to play with yet.