What do you want it to look like?
I sometimes alternate the Hill - Steep/Valley - Steep on low strength but high falloff to give it some roughness. It takes some back and forth with the tool to get something. But, it depends what you want it to look like
Also, since you're editing the land so close to a lot, you might want to use the Mask at a few squares away to protect the edges of the lot. Keep the sculpting from ripping it too much.
You can smooth the masked part gently if you need to- after you clean the mask. :)
https://i.imgur.com/AbSefUB.jpg
https://i.imgur.com/2nvoz2k.jpg