hmmmmmm... is it?Exactly, which means that the Monk has a solid reason to go wisdom....or can ignore it. If the monk doesn't want to focus on Stunning Strike, and would rather spend KI for other places (such as subclass abilities perhaps) and ignore wisdom....that is now an option. Or....they can continue to pump wis for the best stuns. Both are viable, which is exactly the flexibility I am shooting for.
So now (RAW), a monk can increase dex for AC, attack power, initiative, certain skills... and it helps for stun too because you need to land the hit to stun. If the monk invests in stun, they help other skills, stun, but combat not so much.... but still helps a bit, because it does your AC goes up. So most people go dex first, but wisdom clearly is a viable route.
With your proposal, choosing wisdom is now even less viable because the armor bonus is removed. I feel you didn't balance dex and wisdom, you made dex more important....