How to add hills between mountains??

So ive been messing with world machine for quite a while, and the trouble part i feel is that between mountains (Layout generator drew them) feels to empty and flat. I have an advance perlin as well. (Plugged my layout gen into the AP) People said combine them and others said mask. But either way it doesnt work. I also want to have different heights in different areas of the map.

As you can see here i have my mountains but between them they are just kind of flat (As in the fall off is good but not hilly).

How would i set it up in this?

To look something like this:

If you watch from the heli you can see the difference in heights of the map between hills/mountians. How could i achieve this as well?

I think the knowledge gained this time is very important because I am looking for.