If you are doing a reef tank I would forgo the Lion. The Lion can and will eat anything it can fit in it's mouth.
The scooter blenny depends on a diet of live copepods and will not survive in a new tank. They are fish for an established tank usually one with a lot of LR
and a refugium to keep the pod population up
The Flame angel will work in the size tank but can nip at corals. (30g minimum usally recomended for this fish)
The sixline is an interesting fish and will be fine in your tank.
The Clown also a common and interesting fish that will do well in your tank.
The firefish another good choice for your tank. (not with the lion though)
How much LR
do you have in the tank? What kind of lighting came with it?