I would keep him youll like him more believe me lol. He'll definitely eat the clown gobys and when he gets older EVERYTHING except the puffer. I would suggest moving him to your 125 with some tangs and other more peaceful bigger fish. They can get 6" so I would put him the 125. GL!!!!! All the others would be fine except the dragonet without the lion.
the fuzzy dwarf should not be in there already. The puffer will nip at other tank mates fins, and as stated before this is overstocking the tank. if i were you i would move the lion to the 125 gall & put the puffer in there. additionally, as i am sure you have read any fish the lion can get its mouth around it will eat.
Edit: your update looks nice make sure you dont want reef for the 125 because th butterfly will nip at the corals
Thanks. All these guys are going in the 125. Probably keeping the lion in the 30 gallon but not sure yet. He doesnt mess with my yellow tail damsel and idk why cause he ate my other ones and they were just as big