Make "Publish Messages" permission separate from "Send Messages"

While trying to set up something fairly unique for a server I manage, a common "promotion channel" but toggled as an Announcement Channel that rewards active users with the ability to easily share things to following channels in other servers in our community, I came across a bit of a snag.

This is how things currently look right now, and it's sort of odd to me: 

This is the same permission that allows you to actually post in a channel, and it decides whether you can publish or not as well.

Our server already has a reaction role verification system, but I wanted to further prevent potential abuse of the publish feature by limiting who can actually push the megaphone button down to active users (Based on MEE6 level or otherwise), while letting everyone still use the promo channel.

I understand my particular use case is fairly niche, albeit I've been in a couple servers with these sorts of community based channels, but I could see having that additional feature opening up some other creative doors like this for servers in general.