Jagged edges when flattering terrain. Need help rounding off the edges.

I’m trying to have small cliffs with round edges but when ever i use the flatten tool it creates rough edges.
I’ve tried increasing/decreasing the brush fall off and brush power but with no effect. I’ve also increased scale, section size & section per component, all to no effect. I’ve also used the smooth tool but it spreads the cliff to far.

These are what they currently look like;

This is the effect I’m trying to get;


Any help would be greatly appreciated.
Thanks in advance.