To author of this topic I don't know if you are still interested in searching of good FPS, but: „Original Unreal: large levels, fantasy-meets-technology aspect, music from the best of the modscene” Then you can try E.y.e: Divine Cybermancy – futuristic FPS/RPG with great level design and high quality soundtrack. Also story is very good/ Philip K. Dick's style for me. The main level designer of this project was this forum's member Scacky and he did solid work at that time. I still play that game, rough diamond as some people say, and I still admire it. Demo of E.y.e is easy to grab from internet or Steam.