The in-game music is very important. I ended up liking some games not because of gameplay, but because the music was so beautiful.
In my opinion, the music from AoW:SM is beautifully made, but some songs don't go very well with the sphere they're supposed to represent and the game is simply missing a real scary-evil song. Also the music is often lacking those special parts which make you go "oh". I think, the music from Lords of Magic has exactly that and so I picked a few songs that fitted well into the world of AoW, edited & EQed em a bit and replaced some original AoW-Songs with them. I also included 2 combat themes and 2 overworld themes from Heroes of Might & Magic 5.
I chose to overwrite the original Songs, so that the game would play them by itself and I wouldn't have to make custom playlists for every different wizard I play. If you want to keep your original songs, just rename these new ones and add them to the Songs folder. Enjoy!