This is a very odd roster. Good idea coming here for advice. Your unquestioned priorities should be to finish Bane and Balthazar. As @jinbatsu said, Prisca is abysmal, so you need a new 3-star purple ASAP. Also agree that you should work on Tyrum thereafter, as you have no better purple options.
@Olmor is right about your tank. Agwe is weird, but he’s the best tank you have. Gunnar, with his high defense and spirit link might be a replacement, but Agwe has more HP, and that wave could be problematic for the raiders you are probably facing right now. Plus, Gato is a solid option in blue, so going with Agwe let’s you prioritize Gato.
Past that, it gets dicey. Friar Tuck is your best option in green, but that isn’t saying much. Isshtak is meh. Hawkmoon is one of only a few healer options at the three-star level, and she heals all vs. Tuck’s nearby. You really need Belith. She is better than Tuck because of heal all and better than Hawkmoon because her heal also dispels. Leveling both Tuck and Hawkmoon isn’t really ideal, but they are your best three-star options in their respective colors. Maybe, though, you think about doing Gormek in red. You’ve already invested some in him, his special is very good, and his ridiculous HP makes him a nice tank. How many hidden blades do you have, and can you pick up another in Mount Umber next week? If you have four, or you can get your fourth in Mount Umber, I might just think about doing Gormek.
Similar thoughts in yellow. Once you finish Bane, you only have Kailani, and Gunnar now makes her redundant. Gunnar’s defense is great; Kailani’s is… not. You have Gretel, who isn’t Hansel, but isn’t bad. Most four-star yellows are pretty ho-hum , so Gretel stands out a little more. I might work on her - again, depending on orbs. I’m guessing you don’t have many, since you maxed Chao, so this one is a little less clear-cut. Kailani won’t take as many resources or as much time to max. Tough call.