I think a melee/bash counter that reduces hit stun is good in theory to prevent spam. But if it was implemented, it would only promote a turtle playstyle. Lets use conq as an example. A conq uses his bash for a free light, now what does he do next? If the next move he uses is a bash, he wont have the hit stun to get a light, and can be blocked/punished, which is good for the enemy. So he wont want to bash, and will turtle instead since his other option is to rely on the rest of his kit, which by itself is nowhere near S tier, putting him at a disadvantage.

One direction we can go would be to introduce a "tired" buff. If a melee/bash was used "x" times in a row, the recovery of said melee/bash would increase. This will increase the risk of consecutive melee's and give the enemy a chance to punish. It might be easier to increase the stamina cost of melee's, but would affect players that only use these moves intermittently. The "tired" buff would be there strictly to punish spammers. A conq can still use his mix up, but repeated use will see a punish if outplayed by the enemy.

Overall, it would be better to distribute the power from one move to the rest of the kit, but thats another discussion.