I finally decided to create a map for water wars. I call it cityscape because it is made up of many tall buildings (I can't say skyscr@pers on the forums ). Here is the download:
I think you should have like a blue like skylight to make it more bright (minecraft like), and maybe you should up the ambient light a bit, please note I just saw the pictures and I'm going to download the map now
EDIT: Maybe it's useful to say in which version it's made for people to know what they should download in order to play the map
EDIT 2: after seeing this map, I think it's a bit too dark, you should change the fog to a little bit less foggy (about twice as much field of view), and I wonder how this'll play in a match (ctf I assume?)
going off the pics: it definitely needs brightening, Rune has the right idea, and I think you need some more detail, the room in the first picture is too small and is quite bland, while the roof in the second picture needs lots of details.