I also preferred it before the side tunnel was added. First, it looks weird but it also drags the round out unnecessarily as the teams circle each other. I agree with making a passage straight through from the bottom middle area.
My other issue with the map is that with all the climbing needed, one team always gets to the top first. The other team then must fight to try to take the stairs, while also fighting on a weird and tight dome area. I am not a fan of a lot of stairs in general but I guess that can't be helped here.
I don't hate the map at all though. I'm pretty open to all kinds of maps for something different. There are only 2 I really do not like.