Welcome to TF2maps.net
I Downloaded your map and looked around for a bit. The map's layout is pretty good and I like your use of props. If you were to submit this for playtests the biggest complaint would be the lack of lighting. (also known as fullbright). Seeing as you have alot of open sky, I suggest adding a light_environment entity with one of the settings listed on the site below.
https://developer.valvesoftware.com/wiki/Team_Fortress_2_Sky_List
If done right it will make your map look 200x better. You can also use light and light_spot entities to fill in any areas that are still dark.
Also for optimization reasons you should probably use prop_static for things like crates and fences rather than prop_dynamic