You can see about half of the map in the screenshots and the map actually has two levels split at about 70% by 30%. Is only having one level a problem anyway?
I'm not sure if I am right, but since it looks like some sort of CTF map with two bases and those very similar, I suppose you just mirrored the bases. So, since I cannot see many height differences, my guess is that your map will most likely be boring, if not at least for me.
You could get in some additional routes; for example one that ends at the waterfall above the corridor, so there's just a hole you can pop out of. Stuff like that on a different level. Post a layout if you can