Just a few notes, since my lack of time right now. Maybe I'll give you more detailed input with screens later.
1) Bases' and upper levels' ceilings should be higher. You'll often bounce your head while jumping against support beams or similar constructions. Also rocket jumping is almost pointless in there. Maybe be it's intentional, but I love RJing so much
2) I miss a possibility of (of correct?!) reaching the upper level more easily in midfield. It's pretty impossible to re-gain your flag if it goes high and you're on the very ground.
3) The bases seems a tad too open if you ask me. You can sneak around a corner and sniper that doomed flagguard without given him any chance to strike back.
4) Also there are too little ammo, health and armor in the bases. Dunno what's the MH respawn time, but that was the only bubble, despite the tiny ones in the water near flag. Since the base is so open, it doesn't seem to be a defender's favourite map.

Ammo is lacking all over the place it seems (not put in yet?), but at least some rockets and ammo for an alternative weapon should be available in the bases. Armor also lacks, the shards are out of the way and the only YA is more located in the mid, than in reach of a defender. Give those defenders a chance to survive
5) Judging from the screenshots you posted later, I suppose the visual look will still change. That's a plus, but although I like your q4 touch, it may confuse q3 players. Dunno about this really, but could be a problem. But I personally hate maps where I cant recognize instantly where I spawned and what direction I have to run.
Edit: 6) Just forgot, maybe it should be easier to drop down the jumppad in the left side of the base (as seen from the flag). Would be another possibility for flag runners to escape and confuse the enemies.
But I have to admit that I really liked the map and even more the visual style you're currently working on. Would be perfect for a fast , action packed capture fest with a lot of frags and lesser item timing. The quad would rule all of course since the lack of armor, but hey, we all hate the defensive playing style which established itself during the last years of ctf.
Summa Sumatr... eh Summarum: Gute Arbeit Kollege! :icon25: