Any more upgrades will have to wait, the computer, apple care and memory killed my budget for a while. The only thing is that I think I may have figured out what was causing my problems with the old computer - my monitor (26" Cinema LED monitor, purchased over 2 years ago) has been blanking out briefly. I've always wondered if something like that might have been partly the problem (my old computer went through 3 logic boards).
I ended up buying a 17", bigger than what I had planned on, because it still has the express (?) card slot instead of a built-in SD card reader. I'd like to add an eSATA drive dock later on.