I've been messing with my course Nahoon Reef, trying to toughen it up a bit and have been using a great Asset called "Terrain Former".
https://www.terrainformer.com/
It's a bit pricey and probably more useful doing fictional courses but I think it's worth it as it really speeds up all your terrain work. You can have any custom brush, which you can, with hotkeys, size and rotate; great for rectangular tee areas, etc. No limit on brush size as well.
The smooth tool is very handy as you can smooth the whole terrain or large areas to take out the small creases without hurting the integrity of the height-map. I think a lot of real coursecreations have a lot of hidden creases especially around bunkers.
It's also handy to paint with a big brush like this: