I'll start off with a few specific areas in the flythrough build you sent me, then I'll get to the map as a whole.
This is bad for both aesthetic and gameplay reasons. Since the gameplay area (namely the Blu spawn exit) is clearly visible from the railing, it appears that the area beyond it is accessible, which it is not. Also, the ledge can be fired down from, particularly by demomen, even though it is not accessible, and the attackers have to cover quite a distance to get to a demoman spamming pipes from there. Stick a wall there and problem solved.
The supports of the point platform look like they should break up the area into a rough C shape, but they do not. Since there is nothing blocking the players from moving easily through the supports (such as some sheet metal, crates, etc.) the entire bottom areas acts as a big, flat, bland space. The usage of doors is obnoxious. The dark room behind the point creates a small "airlock" space that a. Doesn't make any sense structurally, and b. Is confusing to play in, especially when airblast-spamming pyros are involved. Also, a recurring theme in the map is that your structures are not built to consistent dimensions. The map is full of pointless, stupid little gaps like the one between the brick "shack" at the right and the wall next to it. These spaces are difficult to move around in and hurt the visual clarity of the routes. There is a particularly obnoxious example of this behind A, but I didn't take a screenshot of that.
This area was probably my favorite part of the map in the previous versions, but it is going to be a lot less significant with the changes you've made. It worked well as a stronghold for the attackers just outside of the final point area. With the gray wall at the bottom, and the uneven heights of the roofs (fix this soon, or it could be an optimization nightmare) we see the return of the "inconsistent buildings" phenomenon. The defenders may hold out here for a while, but it will probably fall to the attackers quickly; and since the area beyond it is no longer the final point area, it won't have much use beyond that.
This is by far the worst part. Look at every official TF2 map and every good custom map, and you will
never see a point surrounded by that much flat ground. That point will absolutely not be fun to play on and will become an enormous, spammy pit of sadness, seeing as Red spawns on a high ground from which Blu has no cover. The
trainsition (see what I did there?) from the last screenshot to this area is almost as bad. The little square area outside of what used to be Blu's rally point doesn't look like a good place for the attackers to mount attacks. Any pushes, either from the ramp or the stupidly long and dark tunnel, would inevitably end up being spammed into submission as soon as they reached the aforementioned pit of sadness. That much flat ground, regardless of where it is, is
never fun to play on.
Overall, I think the biggest problems with the map are that it lacks an intuitive layout and has extremely sloppy geometry. Nothing in the map makes structural sense (oddly placed bridges and lots of intersecting shacks and buildings) so it is very difficult to remember areas accurately or forsee what is around the next corner before you turn it. It doesn't feel natural; it feels like a lot of random buildings thrown together in arbitrary order. Take a break, look at Dustbowl, Gravelpit, any community A/D map, or even 5CP last points and compare what they are doing to what you are doing. Then come up with a new layout, or figure out a way to modify this layout, to include your findings. I would recommend that you start a new vmf and remake the map, even areas you only want to tweak, keeping in mind that buildings should be of consistent sizes and should not leave little gaps between then. When you redo the geometry from scratch you might realize flaws in your original ideas, and feel free to throw them out because they sure as hell aren't working.
Good luck.