I note you have Merlin, Hansel and Gretel but haven’t levelled any of them. I know Chao cuts mana but he isn’t in the same league. May I recommend them? They’re fun.
Gafar also has his uses.
On the red front, don’t leave Falcon hanging, Scarlett is very popular for her high attack stat (I would suggest levelling her costume but not wearing it) and Gormek is a mini minion murderer. People also swear by Sumle for his enormous damage, but the miss can be annoying; this is why he is often paired with Wilbur, who I see you also have. Oh, and best get a Boldtusk up. You can’t have too much healer choice.