Treevil all the way. Even though he is very slow, he can be found in most defence teams in 3* tournaments because of how powerful he is. Then Maeve and Aqeela, who are both A level, and Maeve is especially good when paired with Noril. C Bjorn is good too, but Edd not so much.
Tree, Aqeela and Maeve. Not any specific order.
I like Aderyn too but I use her only against heal heavy teams. You can eat An wind, Bat and Morris. They are not worth the space even for collection.
I have treevil, but have not leveled him yet. Eventually. I like maeve, I’m fond of the self buff for mana… But honestly… I hate nearly all my 3*. Not good enough to help in war and events…
Treevil first as, once limit broken, he can really hang in the big leagues. Then Maeve, Aderyn and Aqeela in whichever order you prefer. Gil-Ra, Bjorn and Chochin as outsiders. Morris, Edd, An-Winder & Guardian Bat are useless in my opinion. Do as you will with them.