How can I improve my navmesh for Hills?

I have a huge problem.

My landscape is rather hilly with quite a few trees and my navmesh is an absolute ugly disaster though for the most part it seems that the AI can navigate fairly decently around the map except for in a few spots I found that it is up a little higher.

I am just trying to get it as close to the objects as possible and up around the hills that go around the edges of the map without the AI getting stuck somewhere.

I see theres navmesh and navmesh recast and it seems to have a lot of settings there but I am not sure if its really even helping after going through and playing around with it a bit.

Also, I see lots of separations just like cracks between but during testing i noticed the AI goes through those normally to move around the map somewhat and I also have some blocking volumes to keep the player from going over the hills to keep them in the game play area in the center. I wasnt sure if that was a good or bad thing that it is displaying that way. There are also some trees that the navigation goes up into the middle of the truck which is very strange. I am guessing its all due to the different elevations it looks like and the only thing I could think of is to use blocking and additional navbounds and navmodifiers to try to fix it somehow. Or does anyone know a better way?

I really like my forest the way it is so I am trying not to mess with it or the landscape too much more if possible and after several attempts this seems to be getting closer to what I need.

Anyone have any advice for this that has dealt with something similar or has more experience? Thanks in advance!

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