I know Freak was working on this but wanted to show what I meant by crossfading musics. This is a quick sound I made with a tool called Filmstro Pro and then mixed in with AVS Audio
http://picosong.com/teJ4
The first 18 seconds would be non-combat music.
Crossfades to battle music until about 32 seconds, crossfades back to ambient.
At around 44 seconds it fades to boss fight music. It's a bit more 'heroic' type music than regular combat. Stops at 1 minute 6 seconds.
At around 1:20 seconds it fades to something in between combat and non-combat, or could be light combat/general combat. Who knows.
I'm sure ambient could be slower too.The biggest deal is that all the tracks are the same length and then they can be mixed, slowed down a bit, etc during moments needed.
Not saying this is a priority over anything, but it's something that could add some hype during epic moments and I think it could be added.