Often the best feedback you're going to get is from gamedays. I'm unsure if you've signed one up for it, but it's essentially the only way your going to get feedback on layout balance and team play. People running around the map solo is essentially useless for everything but the most simple of layout problems (e.g. sightlines) and because of that, pictures are the most useful and easiest things for reviewing without playing with lots of other people.
What you need to do is sign it up for a gameday
here and if you don't get in just keep on posting and keep on posting (i've once tried posting on every gameday for nearly a month without getting it but perseverance paid off). Make sure you ask for Source TV. After the gameday, if people directly remember something about your map they'll often leave feedback here.
Secondly, I'm unsure if you've seen this, but our servers have this awesome feedback feature where people can leave feedback
inside the map with co-ordinates and everything, this can be then viewed later
here.
Finally, Source TV is really useful, if you get to the game or not. What it essentially does is re-plays the game exactly as it was done before allowing you to look through a spectators perspective and look at how your map is played over and over again as much as you want. Some time after your game has been tested, the file will appear
here so just download it (it's never more than a few MBs) and copy it to the right directory ("c:/program files/steam/steamapps/
<your username>/tf" i think) and then play it in game using the console command "play
<the demo's name>"
Finally, just because you're not getting feedback doesn't mean your map sucks. People generally tell you if your map is either amazing or it sucks and if it's just plain good or average, it doesn't get that much spotlight. Your job, try and get as much feedback as possible from game days to improve your maps. People won't comment on your map unless you get them to do it.
For some real feedback:
I can see some long sightliness going across the point and either side of it, not sure how you'd fix the ones on the side, but maybe for the ones going across the point, you could have a door that opens and closes to block sight lines across it.