Mosnab,
I've been doing the same thing now since resculpts started hitting the line. If a figure is superior to the previous version, the old one gets moved, sometimes to another shelf into another section, since I have the figures arranged in sequencial film order, or if there's no suitable home on display, it gets retired. Retired figures go into sandwich snack bags and then into big tubs in the garage, safe until the day (oh, so, so far into the future) where I have that ultimate display room where display space isn't an issue. Until then, I have to pick and choose, and I want the best possible versions of a specific character on display.