The smooth function only uses its radius.
Larger areas can not be smoothed out continuously. What we basically would need to create larger (as in: not just habitat-sized) landscapes would be a
huge tool radius.
I have the same issue. I plan to create wide hills for a Bavarian zoo (some day, at least, when/if we will get an European animals DLC).
What
might help (I actually haven’t tried this so far, because it’s one of Rudi’s tips in the linked video which I watched for the first time) is this basic forms tool. I didn’t realize that it can be banked! Maybe, if you use this one and rotate it ever so slightly and just subtract the volume? There will be many such subtractions necessary, but at least the slope will be nice and smooth.
I think, it’s at least worth a try and I will do so for my hills!
