Yes, i would play on a legacy server. I would play a troll shadow priest on a bc server. I'm missing the old shadow priest a lot, and also the old racial abilities. I remember how furious i was when the changed the shadow priest in Wotlk to an ordinary caster (shadow mage).
In my opinion, classic WoW and also BC had stronger RPG-elements than later expansions. I'm coming from table-top rpg such as AD&D, and i'm not too happy about the fact, that rpg elements disappeared more and more from the game over time.