From an outside perspective it seems like adding minimal html text would be fairly simpile to implement. There is already some support for it via notifs and I imagine that only needs to be supported via the xmpp protocol. It even works for 1-1 chats! So why not MUCS?
All I really need is the ability to send preformatted text displayed in a fix width monospace font. /code doesn't work because it tries to highlight the code and it used to work with /quote until the display of that changed.
A feature like this would be really useful for people who are writing bots.