I personally love this mechanic, it makes the game more interesting and difficult. I don't mind the mountains loosing dirt on the steeper sections, it seems more realistic to me anyways.
The lag spikes don't really bother me, they are usually only in the beginning anyways. Unless you constantly travel near mountains.
As for mountain bases, I haven't really built a mountain base yet in VS
It would be nice if they would add a option to disable this option for all but players. That way you still have it, but not without your personal actions causing it.