A sniper at the end of those corridors will slaughter all who enter. Building with windows looks too thin, stairs looks too steap. Lighting is ok but surely you could have some more creative architexture?
It is interesting to see an open flag room like this, it reminds me of a lot of red faction 2 maps, which played rather well. Such as the original well also, not so much the newer version. It would be nice to see you fit the TF2 theme strictly as there is little variety in your texturing.
Is looking rather linear. Side routes welcome.