They had something like that planned for Divinity. Hopefully it will make it into Riftrunner.
From mp3 description list at
Merry Christmas and Happy New Year from Larian Studios!Original file name: Fightdrums3
This piece was created as a prototype for the interactive music system we intended to use in Divine Divinity. It demonstrated how things could sound by combining a series of different tracks/patterns depending on the situation. This particular piece was an example of developing combat situation. Sadly we never found the time to implement the system.
