You still can. If you got the Ragnarok Magicite in Narshe, it'll teach Ultima. Or, if you didn't, I believe Celes learns Ultima at a high level, so if you get her to that level and learn everything else, she'll (obviously) have every spell.

I thought the number of coral was around 40, but I really don't know. As I'm not too fond of Strago or Relm, and you don't really get anything out of it except one Lore, I think it's somewhat pointless.