The main problem with this map is the lack of routes to the points and the fact that some routes are just too narrow.
Point B's side route that goes around back, for example, should be expanded or at least widened, because imo its already a fairly advantageous defensive position that the attackers have a hard enough time breaking into it. The other side of B seems fine.
Point A could definitely use some kind of help for the attackers, either some side route that allows them to gain access to that high ground area behind the capture point sign in the second picture might help a lot. Right now it seems to closed off to make it a contest.
The last point also seems geared heavily in defense's favor. The vent access behind into the little ravine area doesn't seem to do much because the vertical advantage of the defending team generally outweighs any push from that area. I would suggest perhaps some battlements on that building that face the bridge so that offense can contest the bridge without necessarily having LOS to the last point might help, and would offer more routes for scouts/soldiers/demos.
Other than the choke point issues, the map looks really good, but it just seems to delineate to a spam fest when it comes to the choke points, which is something gravel pit can avoid pretty well by having multiple angles of attack for each point.
Also, I'm unsure, but can you jump on the roof at point b? I never bothered to try but didn't see anyone during our gameplay. If not, you might want to consider making it possible, as things like that tend to make for good battle areas.
Hope this helps.