Why do you still only see team with OBW or spiderman 3* for those that can afford him? , why do the wolvie/daken still appear so much despite not being overpowered (Ares dealing a lot more damage for instance).
DO the dev know why? Because they are the only character that can regenerate or heal, and as such the only needing heal pack for accident (board/cascade) but that can be played without having to change team every 3 fights.
All the other chararcters, if you do not have a good board will take damage every fight, and after 3 or 4 will become useless (get killed in the next fight).
The questions is what is planned for outside of fight health regain, you cannot go into this direction further, or you will need to redesign all your PVE (or no one will complete the events) and the PVP progression zone, as you won’t be able to gain enough point in one run (so before going on a break and getting retaliated) for a shield to be worth it.