collision

The main base is a bit large, could be trimmed on the side farthest from the main ramp.
There's a very tiny hole in the wall for Zerg here at the natural. https://i.imgur.com/P20YFDm.jpg
At first I thought some of the areas were too big, but I believe the intent is that large armies must go all the way around the mineral walls to efficiently attack?
The korhal walls might be too tall, I don't think players will recognize them as air blockers.
The mineral walls might be too big in resoruce for them to be used, it would take far too long to open  up for it to be reasonable. A considerably lower resource amount might pose better results. If you want to keep them at 50, I'd open it up by three patches or so like you have the center. I'm worried this just becomes a turtle map/rush to sky map otherwise.