I agree with you about Kelile. She was given a nice buff a few months ago that has gone largely unnoticed. She’s a very solid 4* sniper now.
Some others that come to mind:
- Danzaburo - the little badger has two parts of his skill that are 5* quality, and then the “oops” one-third of the time. He can be very impactful if you’re lucky.
- Kiril - perhaps he’s not underrated (7DD’s guide does put him at A) but I don’t hear many people prioritizing him. He’s a 4* you’ll use forever; I have two maxed and used both last war against red tanks. Sturdy as rock, and his buffs and heal are not only welcome but reverse any -defense and -attack ailments you’ve picked up.
- Sabina - Everyone loves the other purple 4* healer, Rigard, but Sabina doesn’t get much respect. She does huge tile damage and a solid heal. But the big bonus is the debuff against your foes. She’s a great candidate for those Sorcerer emblems (who else are you putting them on?) to create the equivalent of a 5* healer/debuff – which is a very handy skill set. There’s no 5* hero that can do a whole-team debuff without first hitting, which can be quite painful if you’ve let Elena or Boss Wolf set up a riposte.