Here is something helpful:
Your ramps are too steep and narrow. Try making stairs for steep places. The normal is 8units high, 12 deep... and width around 110-128 for normal stairs. When you finish that, use the clip texture on a different brush, and clip it to a ramp.
Also, you should widen some of your hallways. Spy's don't enjoy bumping into people and its really hard to avoid someone if there is only room for 1 person! Use a prop_static and the heavy.mdl as a reference for determining width of hallways and stairs, and how tall things are. Don't make them too tall.