I get it, thanks... wasn't sure how you were generating the mountains, and that is indeed the least intensive method.
Perhaps be able to select/deselect in config.lua which ores to cover? Like, it seems kinda silly to have to remove a mountain in order to get to some stone or sand deposits. :)
Personally, if I was doing it, any single lone deposits I'd drop would never be more than 100. Think of it as just an indicator of what's there... yer walking by, find a rock, and think maybe there's more in there.
Perhaps, a config option to choose how far the small-rock field extends from the mountain/ore deposit? Frankly, I could do with it extending further out and being rockier... make it worse. :)
(I am tossing around an idea in my head for one of the mods I was interested in making, and using your mod with it, opens up additional possibilities for something else I can do with one of them... just gotta get around to actually making em. :) )