That depend on what kind of piano musics would fit with the ambiance/atmosphere you are looking for.
Doom for me always seem to be focused on 3 categories of music.
Rock,metal and maybe techno wich represent the fast paced action.
Dark and atmospheric wich represent the demons/hellspawn and hell.
And in some rare occasions musics that doesnt fit in the first 2 categories.( an exemple being Pharaoh/map 31 of TnT Evilution wich is a piano song with a kind of sad tone)
You should check out the music wad i compiled,some of the musics in it is pretty much just like the one you are talking about,give me your toughts on it.
http://www.moddb.com/games/doom/addons/ ... -music-wad (only work with Doom 2,Plutonia and Tnt wad,i didnt made one for Doom 1)
This music wad is for a project/idea im trying to start,if you are interested you can check it out here
http://forum.zdoom.org/viewtopic.php?f=4&t=45521