I'm with — A bitmap font that lets us use different colors, font styles, behaviors, etc. in a single string would be awesome. Here's an example from Marty's Fun Tumblr:
“Regular Text|||| [w1][c1]Color Test||||#[w0][s1][c4]Color Test2||||| [r]Regular Text#||||[c9]I’m a dialog box!”
(what do you call these btw? string/text codes?)
Here is a slightly cleaner example from MMX:Corrupted's dialogue editor. Give it a minute.