Looks really solid and it doesn't seem to have much screen lag.. screen lag=unplayable

 

I really like the layout and the clean, consistent aesthetic.
The main suggestion I have it to try to replace the lazy cover in the hallways with something more substantial, or just remove it. In general, you can probably get away with just having a crate, vending machine, or something else on one of the corners at each end of a hallway. Get rid of the stuff in the middle of the halls. It's not really needed, and is more of an obstruction to movement instead of serving as cover for battles.

 

Sorry, I just realized I never responded to you last post.

I don't mean for this to discourage you, because as I already mentioned I like the design, but the changes you've made have done very little to alleviate the concerns I expressed in my initial post.

Let me use your screenshots to explain what I'm getting at:
1st Screenshot: The cover piece next to the plants is completely unnecessary, and looks out of place. If you feel like you need cover there, you should extend your wall out further so that it ends where you cover piece currently ends.

2nd Screenshot: All of the crates on the right side of the hallway are unnecessary. If you feel like you need cover there, you should extend your wall out further. I don't mind the ones on the left so much, but when you have them on both sides it restricts players movement to an extent that just not needed.

3rd Screenshot: Same as the first two. A crate may be acceptable on the left side for cover during battles. Everything on the right side is unnecessary. If it feels to open there, extend your walls to make the space smaller (I don't think you need to do that though. It should be fine without those cover pieces).

4th Screenshot: I see that you've removed the pillar that's shown in this screenshot. My only suggestion for this section of the map is to reduce the amount of glass. If you've every played Halo 3 maps with shield doors, you'll know that they create a game of cat and mouse. The glass will have the same efffect. It's just not a type of gameplay I enjoy, personally.

Last Screenshot: Again, the Torque cover pieces are unnecessary. Another note on this screenshot...I see that you've used 2 foot wide walls almost everywhere. I suggest using a minimum of 4 foot wide walls. 8 foot wide would be better. This allows players to use the walls as cover, so you don't need to add more cover pieces.

Not pictured: I feel like the Truck and most of the Cargo Containers are also not needed. They make the map feel cluttered, and it will function fine without them.

Final Word:
- Eliminate all of the cover that's on corners, extending the walls to replace them if you really feel it's necessary.

- Eliminate the Truck, and most of the Cargo Containers (at least the red, blue, and Violet ones you have between the Truck and Overshield.

Overall, I'd work at making the design/structure of the map serve as the cover, rather than adding cover pieces after the fact. You have good enough structure to this map already to make the various cover pieces totally unnecessary.

- Thicken up your walls. This will allow players to use them as cover.

- Reduce the amount of glass in you Creature Tank area. I would also probably pull that whole section in closer the center of your map, shortening the longish hallways leading to that area, but that's your call.