Edit: I realize this is sort of a showcase but for us this is an issue we've been trying to tackle for awhile...something I've seen others post about and so I thought I'd share our progress to add to the conversation.
We've been dying for decent trees in Enscape. We tried SpeedTree->Archvision but found that we had little to no control over the custom RPCs (can't hide leaves, manage visibility graphics).
We've settled on a SpeedTree->Dynamo->Revit and SpeedTree->AutoCad-> Revit hybrid that allows for both hidden line graphics control and Enscape as well. I've attached images of our hidden line tests playing around with leaf density....the autocad imports render mesh outlines only...which make them ideal for hidden line views...where the Enscape mesh would otherwise draw every single polygon and turn into a black mess of lines.
We've just begun to work in SpeedTree but the ability to craft trees that look like our local species is HUGE for us and clients. We have tons of wiggly Live Oak trees in Houston and none of the trees I've seen available to Revit users comes close.
We are pretty happy with this direction because though the file size is big (we always have to be careful...but we're becoming clever about ways to reduce size) we can make vegetation that looks like a recognizable tree and not a generic tree-like thing! I guess we're tree snobs....that said all of these trees are in progress and you can see the holes in the tree meshes due to us using trial software....
Another thing you will notice is that we're using generic leaf materials (green) and simplified meshes for leaf shapes. SpeedTree is wonderful but generates heavy models...so we end up hiding most of the twigs etc before exports.
I'd love to hear your thoughts on this ...this route takes time and I'm basically becoming a tree modeling guru...but it's produced the best results for our purposes.