Currently, if you have two views open for the same file, if you change the syntax coloring for one of the views, the other switches to match.
I would absolutely love to be able to set each view independently from the other.
My real-world example:
I’ve been working on a fairly large HAML document, and roughly half of the document is actually JavaScript which, of course, gets no coloring because it’s inside a HAML document. It’s a pain having to switch back and forth just to get the coloring, so I don’t bother. But that feature would be a perfect solution.