Much like the Orchestrion can change the music played in the house, i suggest that a furniture item be added that allows you to change Battle themes for every region. For example, should you want to play Quicksand, the 1.0 Thanalan battle theme, in fights in Thanalan, as long as you have the Orchestrion roll for it, you should be able to change it. Same for themes for Coerthas, La Noscea, The Black Shroud, so on and so forth.