UNitrack is the last thing you want to ballast. The track is too high.
This is what we envision in our minds which Fine track and Flessman can support.

Those of us that use unitrack this is what we don't realize.

Kato's unitrack is more in line with this configuration

Where the ballast is above the basic terrain. When we try to fill the gap it looks funny.
Just imagine if the ballast was filled to the edge if the road.
The ballast should not go out but a few mm from the base. Unitrack is hard to do correctly. They should do away with the glossy ties too.