rooted in 2E D+D. sell me 3.5E or 4E.

our group uses the 2E rules for all of our gaming, including many "house rules" developed over many hours and play sessions. this rule set is wonderful(for us) and suits our purpose. a couple of us were wondering if it was worthwhile moving up in editions. my biggest fear is this: 2E rules serve to develop the story, and it seems as if the story takes a back seat to the rules of the higher editions. am i close on this? seems to me that 3.5 and 4 are doing their best to simulate "power gaming" and compete with WoW and other MMO's. please give pros and cons, especially if you have moved on from 2E....