I agree, and would also implement something along the lines of passives on some Stun Immunity monsters:
That way, if both Stun effects and resistances are reduced, Stun will have a wider chance of landing although it will definitely not have the same chance to easily swing a match.
Let’s look at Raizen and he’s insane: if you land Stun Blitz+Stun Retribution, your match is 90% won.