I didn't design this to any 9vs9 pub play, small games like 3vs3. At the beginning i was going to design low route, but as you can see i didn't really do anything like that. But now i could add new route going low, maybe making it dsm route. Maybe make it open when there's over 6 people?
I think given the current situation 5 people a team would start to cause congestion... 9 would be chaos. I agree with you that 3 would be good.
Maybe you could make another map like this one, with a few different routes and the whole map generally bigger. Call it something like 'Greater Shadow' and make it 7 a team.