Yes, those 5 are also the ones I think that are a bit over the top (
Korvash, Tentaclot, Killgore, Tzu, Nevamor)
From the 5 I'd say Korvash is the most OP and Nevamor is the one closest to be OK.
I'd also add
Loralei to that list; she is okish but her level up isn't... 2 extra cards with no condition is absurd... when the other team has no answer for her Defense 2 and she levels up early, that's the start of some miserable games