Zip I have looked at your map and your well on your way to a great map
Everything in the map screams this is mapping fundamentally mastered...lol. I was very impressed to see chaulked unseen faces, textures of proper scale/rotation, and a good basic layout
As far as adding static models like bushes/trees, go for it. A map this size can get away with lots and lots of detail
Areas that need to be looked at:
(1) if the inside of the fence will only be seen then chaulk the back of the fence poles and use the no draw texture on the back/top/bottom of the wire fence.
(2) Back of medic sign could use chaulk texture.
(3) Handrails into buildings need the textures rotated on the sides.
(4) This is a hard one.....texture alignment of the curbs made my a square cylinder to the matting brushes.....just something you have to play with till it looks as good as possible
(5) Doesnt always cause a prob but your func_ladder brush should not touch anything...have it off of all faces by at least one grid block. You will find this more of a prob on weird angle ladders not the common angles.
)
)
! That must be one huge map! 8)
) and thus reduce its triangle count. Moreover LOD terrain has efficient culling for invisible faces.
.