Should I pull for this Sunfish right now?

Honestly, the Sunfish isn't that useful! It's just a special collab character + an Ultra Rare with a slightly longer attack range. Still, it's special, so I pulled for it, but it'll probably come back again someday!

Since the Coelacanth is basically a regular rerun every year, I don't think you need to push yourself too hard right now.

The coelacanth comes every year, and the characters aren't that great either... no need to bother.