I've been looking into it, Rodimus. I spent the morning working on how to widen the windows in battle, which would be a necessary step.
There are quite a few more logistical considerations here, though.
The obvious, and possibly easiest is the "need MP" window. I can make it smaller, and probably shift it to the right a bit, but I'll have to rearrange its contents in order to make any of that not look weird, and I'm not quite sure yet how much hacking that will require. I may have to rewrite the entire routine that draws that window (ugh).
The less obvious but possibly more serious problem is the amount of RAM devoted to the spell lists in battle. There may not be any wiggle room at all, which would pretty much make spell name expansion impossible. I don't know for sure that's the case, though, I haven't really gotten that far yet. Another issue in the same vein - assuming there is enough space in RAM for longer names - is getting the names to actually display correctly once they're expanded. What I was trying to accomplish (for my own purposes) today was expanding command names by one letter (which I thought you'd also like... "summon,
?). That's proving to be a much tougher proposition than I ever imagined, and that doesn't require realigning three entries per row...
Like Grimoire LD mentioned, if you can live with abbreviated names in the spell lists but longer displayed names when the spell is cast, that's pretty quick and painless. A more complete solution is going to take quite a bit more time, if it's even possible at all.