Ability to limit mentions per channel / server

You can disable @everyone, however that doesn't deter some trolls from mentioning a lot of people one by one. It is already limited by message length, however it would be nice to be able to limit the amount of people you can mention in a single message. It wouldn't stop trolls, but it would make it harder for them.

Combined with Slowmode you can minimize the flood of Users asking "WhO pInGeD mE?!"