I enjoyed the map, and it looks very nice! It did feel a bit easy for blu though, so I have tried to address this in my suggestions.
I'm not so sure about my idea for it on the right, but I really don't think blu needs that entrance on the left. It just allows blu to get behind and completely dominate with the high ground. Red does not have much chance of defending other than staying at the very corner on the point. I made a red circle for where you might want to put some defensive positioning for red.
The limey outlines suggest using the house to go up in to the rock, and use the cliffside as an exit. Entirely up to you, but I would really like that left entrance removed.
Moving on to the next area, blu has a lot of control here too! Red has a hard time defending anywhere effectively.
I propose that those stairs at the back be used as the one route to get to the single upstairs room overlooking the roofs.
Add some fake doors or something inside so it feels like it has more purpose, of course.
The red outlines the new buildings, pink the new routes. I think the pipe for gold is a good opportunity to situate a defensive but 'functional' building for red.
(I drew the spawn vis in for myself)
I really liked this part of the track! It looks nice
Dead end buildings make me rage! They're not even providing an overlook somewhere, they just hold health/ammo. Just close them off altogether, or use them as connecting parts (like you did in the very first area).
In regards to your post that you just made about the new platform!
This is the view I have from here, it's very targetable from many blu places, and not very desireable to hang around here long. What harribo said holds true, it's not use too often, and neither is that flanking route that continues on the left (which I will get to in a minute). You may want to move the track up here to make it used more - with an obstacle such as a small building (extend that deadend building of yours maybe?) as a reason for the track to loop around it.
Just something small that you should take a look at
The final area of the map I felt played very well! It was definitely a challenge, but a fun one. The exit we see here on the right is that side route I mentioned, one that doesn't get used much. As we see here, it's not going to be use much as it's narrow and straight in to red's firing line. It doesn't offer much in the way of area control, as the left route has upper ground, a flanking route, and more space for avoiding spam. This exit would maybe be better coming out of the wall where the computers and that screen is. Currently it's only really useful for red to get behind blu, but even then blu can keep an easy eye on that route from their cover on the left. If the intention was for it to be red's route, then give them some sort of drop down entrance from the south of that image, and keep it as is; otherwise you don't really need it. The rest of the last area I think it's quite safe to get detailing