I hear ya and in he same boat. I'm currently looking for new games to box now myself. I'm use to boxing a full group and scared that the newer games coming are using graphics engines that are newer and take alot of resources out of the box so i would not be able to box that amount on a single machine like I do WoW.
I dont want to buy another computer for the sole purpose of boxing a set amount of toons to keep my performance somewhat high...