Sounds great. I’m guessing this is the finished product of the work being donehere? I’ll have to try this out on my terrain engine until we figure out how to merge each of our terrain engines. I can easily mesh it with my terrain texturing algorithm to make it alter vegetation density or other properties appropriately.
Have you considered just preloading a couple hundred or so procedural trees? You could do a rotation where when one goes out of range it becomes eligible again for placement. With that enough possible trees and no two trees in sight ever being identical I think it would be impossible to notice repetition. You could also regenerate some of the trees over time as you transition to an area with a different style of vegetation.