Had a quick look at your map. Here're some things that caught my eye... COMMENCE FEEDBACK!
. Generally, the indoor areas are very mazelike IMO... and there are hallways everywhere! It feels like there are plenty of hallways going to random, unseen places not really leading me anywhere. There is no easy "fix" for this, so all I can say is to try to simplify the layout a bit by removing potentially unnecessary hallways. Also, if possible, make them more intuitive(?). Anyway, here are two routes that I think needs to be dealt with:
Route #1 - You go in here:
Out here:
This first route is opened after capturing A, but it leads straight to the B point?! This is super weird as the cart goes on a longer track but you can skip it all by using this route. It's going to make that A->B route awkward to play, I think. Having the doors open AFTER you cap B solves this problem quite nicely.
Second route... you go in here:
And out from here:
This second connector/route/hallway is open right at the start, and leads up to the A->B route. This gives any BLU players using this route a huge opportunity to flank the defenders. Suggestions: either remove the slopes leading up or make the route open after capping A.
I feel this whole section around A and B needs to be a bit more controlled or restrained (less routes, less chaos). Players, especially scouts, spies and pyros can way too easily flank the enemy at any time.
Next picture:
. This might be a too powerful a spot for the sniper. This sightline is somewhat long but the flatness of the area will make it super easy to pick headshots. You could try to raise those obstacles you got there a bit, I dunno?
. Small things about BLU forward spawn. The doors could use bigger triggers as you are able to bump on the door before it opens. Also, add a light or two to the spawn.
. This thing caught my eye. Why is it so brightly lit? Is there a secret door behind it? It's a bit odd, but certainly not a big deal.
. This balcony thingy here could be made a bit bigger to give more room for attackers to maneuver once they've walked through the door
. This tiny rail is silly. There's no need to have it there. Removing it will make it easier to move from one platform to the other.
. Lastly, make the enviromental light a bit more neutral white-ish color. Right now everything is quite strongly tinted (lighting can be tweaked later on)