Hmm yeah I have mixed feelings on this map.
Firstly, I think it could be really fun and the layout seems really decent overall.
But I think there are too many problems, some of which are just personal preferences. The small stuff:
I don't like the Egypt setting, not that you detailed the map poorly or anything, I just don't think it fits with TF2 at all, even when combined with some of the spy-tech/secret base stuff. This is just personal preference.
I don't like the big pool of water in the middle of the map. I think it's unnecessary and very awkward for flow. If you're worried about a safe place where Pyros aren't as strong, you have plenty of health packs everywhere that a player on fire can easily run to one. Other than that, I think it just ruins the lower middle area of the map, it seems awkward to have a big pool of water there. I tended to avoid the water because I felt too vulnerable going through it and there was really no benefit to it, not to mention how my movement changed while wading through it. I would remove it personally, but again this might be personal preference.
The main problem I see with the map is the whole cart system - hell, not even the cart system but the horribly long, drawn-out stale mates that happen when both teams have the flag and just hide behind their spire with sentries and an entire army guarding this easily-defended area. Especially when teammates clump up to guard the flag, as soon as it's dropped it gets picked up again. That whole flag mechanic is clumsy and is counter-productive to the other anti-stalemate mechanic (the cart) you have, and instead seems to completely negate it. The people who played on the server were thoroughly confused why they couldn't cap the flag, and instead just decided to defend instead of going after it, resulting in two very long games of sit on the flag, which could have been a lot more dramatic and dynamic. This isn't really personal opinion, as pretty much everyone on the server expressed roughly the same opinion. I would say this mechanic of capping only if your flag isn't being carried is the weak link in the map.