Haven't figured out how to consistently trigger the bug, but this is the main breakdown:
- Create a new freeplay world with Space Age, its dependencies and RSO.
- Enter editor mode and fly around.
- Patches will occasionally have their edges flattened; this can range from a slight flattening on one side to a dramatic cut that makes the entire patch appear almost rectangular.
I'm not certain beyond doubt that this is an issue exclusive to Space Age, but I haven't been able to reproduce it at all with only RSO active.

Did you increase patch size in some way?
This is in general a result of the way that RSO works and I think 2.0 changed something that makes this more visible.
And it's not something that is easy to fix (if at all).
There is also an issue with ore being placed on cliffs which I think has similar underlying reason.

All world generation parameters were left entirely unaltered.
Had suspected this was one of those tricky-to-fix things, but figured I'd chime in regardless.

Ohh actually wait - I might have caused this by one small recent change. I'll try to revert it at least partially.

Please try with 7.0.5 that is up now and it should have less hard line resource cuts.

Did a brief flyover and noticed much fewer hard edges, and more cases where a few ore patches of the same type show up in an area. Seems to have made an improvement.