I think you should put most of the work on last point, the mid was fine and second could be tad bigger so it is not that easy to hold with sentries and soldiers. Last however was pretty terrible, there was spawn door with resupply right front of the last and demomen and soldiers kept spamming on point and attackers couldn't do shit about it, there was also only two ways to the point, one begin rather cramped and making you easy target to defenders and second point was next to huge deathpit and lead right front of enemy main spawn exit.
First of all, last needs to be less cramped, it is small, it is covered by boxes, barrels and big fence making it easily camped by demomen, second problem is that how easy it is to airblast/explode/push into pit while they use lower route, you need add rocks on the cliffs to prevent it begin so easy, redoing those spawns wouldn't hurt either. The upper route needs to be wider for sake of both, back caps and attacking the point.
It is certainly fun map tough.
I think that is all i got for now.