3.5 was pretty easy to break, I used to make broken character builds in my spare time (however I respected the system enough to never USE any of them)
I did optimize my feat choices but I never went through with breaking the game. Closest I ever came was with the 3.5 update of the Shifter class, they "balanced" it and it seemed ok, until you have some jackass like me running it and choosing Assume Supernatural Ability (feat) for the Beholders Eye Rays(Which you get all 8 rays for 1 feat). So now you have a Beholder on your team. The same can be accomplished with a straight Druid with the proper feats and that is even more OP because then you have the Druid spells when your not in wild shape.(Or take the supernatural ability of the Choker creature for the ability to cast two spells per round.)
Druids, Clerics, and Wizards man....
However, if your group respects the system they are using, they should be there to play and have fun not shatter things into tiny pieces.