Having had a better look inside the game, there is indeed a lot of improvements one could make over the map to make it more fun for everyone. All three check points and some of the routes between them come off as confusing and don't offer much in terms of game play variation. I will address them shortly, but start by examining the points themselves first:
Final Capture Point:
This area is very tight. Very spawn campy, and not a lot of play room or head room to the area itself. The defending team has the advantage here. There's no height variant to the map and the ceilings are low. I would examine some of the official valve maps like Badlands or Gorge to get an idea that it plays better for the attacking team to not have direct access to the point. Even coldfront (non official) forces the defending team to spread out between the doors and has a huge variety of game play area that compensates for multiple classes (like a place to have engineer set up, sniper to use his skill.
A typical size of this area should be around 2048 for the areas leading up to spawn and the point. This area is cramped and will result in just letting the defending team spawn camp to win.
I can't offer much advice on this one for layout changes. It needs the most work.
Mid Capture Point
This area has no dynamic game play to this area either. Its a rather square room with two doors that meet in one area, and a simple ramp that leads to a over looking area. Its bland, and doesn't offer much for other classes. Its flat, and again has no height variation to it. I have given a few simple suggestions to this area to help that this helps:
Lot of my suggests refer to size issues. Your area right now is 768 by 1028 for the main part of this room and feels cramped. Because its flat, I drew in a suggestion of a upper ledge that changes the area slightly. I have also suggested that you remove the ramp completely, as your players already have a viable way up there (jumping up from props in another room), but even more so my suggestion refers to changing the location of the two entrances to this room that merge from one area (yellow being where that one path exits, and the red being another where that exists - I will explain that later when I call about that hallway. I also don't feel this prop should be in the middle of the room but against the wall for some cover for where the red path now exits/enters. This may help a bit; Height also needs to be increased by at least 256. I also believe you should think about changing where the capture point sits in this room in reference to height. Adding the space will allow ways around the point, and allow teams to have a different play style.
Its your map after all, and these are only suggestions.
Second Point
This area is huge and needs some fixes. One for optimization, and more so for updating the game play of this hill. The problem is that the attackers actually have a huge advantage. Typically, the players that have the higher ground are more likely going to win. Its not a dramatic advantage in this case, but its something to be thinking about.
Secondly, and this is important, that a defending sniper can cover all these doors. There's no cover and no location to exactly where players will come from. Its not flat, but the area is wide open. Adding that fence didn't help much to the layout. In fact you should consider cover, places to put sentries, and where snipers will typically attack/defend from. Honestly this might be one of the harder places to play.
My suggestions:
Optimization of this area will help by adding something to break the direct line of sight. Let's start by adding a building here, and putting a func_detail roof on the top. Then have a skybox brush travel through the func_detail roof. Clip it off and this will break up the area a bit. Later one when you read about occulators and hints, it break this area up a bit. Players don't need to see all these doors at once.
Now for more layout detail:
You'll notice that I altered quite a bit (why I posted about optimization separately too).
The area isn't directly a hill that leads from 3 being a upper part to 1 being the lowest anymore. Instead, I offered some imaged explanation of changes to this area to help game play as well. We will start with the door changes. Much like the last area I altered, I started with switching the doors for the two paths aforementioned. The yellow and red arrows for the areas. You'll also notice that the green area offers a battlements or ledge area for snipers on the attack. This will indicate to players to pay attention to this area.
Now, I want to draw your attention to the crude dark green lines. these areas are cliffs or drop downs. Its to break up the path players would travel. You'll notice that there are two on the map. One is for making that battlements a harder option to get to, while the other one, makes it a natural ledge for snipers, as well, as an area that breaks up the action of players running circles around that rock near door "1".
I also added a red ramp that engineers could build sentries on to cover the point without being on it. This is optional. Most of the while areas are either fences for cover, or props for cover.
The main area now has several height differences, but the grass area should be as such: The grey'd purple "x" is the highest area of the two circle areas. It should be a minimum of 80 units in height. This will had a bit of cover the two areas. This hill isn't the highest point. In fact the green sniper battlements should be the tallest, the point and the two cliffs next (plus the red ramp) and the x-hill the third. I can't give you exact numbers on this, so you'll have to play it by ear to get a feel for things.
Again, your map, you decide how you do things.
Connecting Paths
This one way door has no indication of when it opens at all. I had to capture a few points to see when I could gain access. Generally I am not a fan of the one way door, as it will become a feature route of the team as its the most protected of it all from Final to Mid and Second! This will be an issue. I would look into removing it.
These two paths leading into each other don't change much to game play. Its easy to cover both of these preventing pushing into the mid.
Another weird wrap around for the map. If you get to redoing Final, attempt to remove one of these doors as it offers nothing to game play.
These two areas are confusing. It took me a few travels to understand what is going on here. These paths feel confusing and a real simple solution to fixing them would be updating them to merge. This is the only path I have a full redo suggestion would me merging them in a way where the upper path over looks the lower path. Since I suggested changing locations of exist, players may understand the game play advantage if the upper area was limited by where you can enter (once from cap B) and another from Mid possibly or from the prop ramp you have posted in your map (near mid).