to make your flashy effect use a point_spotlight or a env_sprite with renderfx set to ConstantGlow and rendermode to World Space Glow, don't forgot "Start on" flag.
Your maps look crazy to visleaf Try to use Hint brush for divide each part of map in as a closed area.
In first part, each part of building area.
In secund part, Each 'inside' hidden part o building like the staire area of the main building o your first screen.
use LOD for each model with your fog effect.
finnaly group all building detail bursh into func_detail or check you map in glview to see what brush turn you visleaf crazy. then turn it to a func_detail.