make flag platform larger, more total area on the top, also make it higher off the ground with steps so that long plasmabombs aren't dominating, they already are really hard to deal with and are a bit of a pussy tactic, adding crates or a wall to hide behind would interrupt the flow of the flag room so IMO It's better to just raise the stand so that people will use that, Also I'd like if the curve on the wall directly across from the flag was removed as it intereferes with grappling, if this is an aesthetic thing maytbe you can just clip it so that it doesn't get in the way.
finally, the wall near the steps exit is very low and makes it a little too easy to skip out on a freak grapple, the map is by nature pretty hard to defend and I think that wall was a major help for the defense since offense had to think of a way around it, it added a tad more depth that I htink is lost in 3level2.
also I know none of these are your problems rav as you didn't make the map yourself so :P
It's not that poorly textured or whatever nad looks decent, I personally prefer the bland grey/brown of 3l1 but that's really just personal preference.