Ok, updated it (and found a bug, players can get stuck crouching close to a snowed crate...).
Here are the changes:
VISUAL
-Inverted specular on snow. No more massive blue reflections
-Fixed a ground texture in ladder CT spawn
-Fixed a concrete texture in B
-Lightened environment shadows
-Added a rail in skylight room (B) to help players notice unreachable area
-Changed the middle vent red light to a blue in order not to confuse newcomers (not a reachable area)
-Made lower steps of A stairs smaller
-Fixed decals being applied to displacements
GAMEPLAY
-Lowered T's entrance platform in A
-Inverted windows wood in house A to facilitate CTs job covering stairs
-Added a fence on A corner to lower in order to prevent cheese position
-Added an additional box and wood planks to mid A corner in order to increase predictability
-Made some lights nonphysic in order to prevent cheese positions
-Fixed map boundaries and abusive spots
-Added a black brush in lower crate A to prevent abusive spotting
-Added a wood plank in CT spawn to reduce CT's fire angle. It made it difficult for T's to spot them in tubes
-Fixed a collisions on a model down A vents that disturbed movement in barrels corner
-Lightened environment shadows in order to help readability
-clipped and resized window brushes on CT spawn to B to increase prediction
-widened a wood plank in middle to help throw grenades
OPTIMIZATION
-made func_detail some missed brushes
TO DO (Among others)
-Further testing of the bombspots with good awpers & smoke strategies
-Change middle door for a breakable model
-Observe lightmaps in order to improve shadows and reduce filesize
-Revise hinting, as in some places it may have aged
-Design and add new signs for bombspots
-Improve some textures (mostly specular and ssbump)
-Improve 2d & 3d skybox
-Further details (v.g snow on few props) & light improvements in certain areas
-Further clipping to make movement smooth
-Navigation mesh for bots