I think that would be a cool,but not to replace image-boards,but rather as another way of communicating online.
I think pseudo-anonymous websites would be cool, this sites when they get big get misleading and just annoying.In popular sites like 4-chan people don't say be B in response to A ,they say D ,Z and C in a ironic way.I've seen people who respond the most retard responses they can think of only to degenerate the conversation. With this system you wouldn't have glowniggers spying you,but could also differentiate the users.You wouldn't talk to your grandma the same way you talk to a friend , so the same online you wouldn't talk to a newfag the same way you would talk to someone who specializes on the board topic.
This wouldn't replace the imageboards,because this is not their intent.Their intent is to have meaningful conversations or discussions,while imageboard would be for laughs and idiot posting.
Agreed bans are stupid
Can't you see there is a solution,different boards,(or pseudo-anonymous forum as I mentioned),with different owners.Maybe in one they accept what you hate maybe in others no.The idea is that there is a free-market of ideas and sites in which the user chooses the best one instead of being imposed.