I’ve been trying it out, and here are my thoughts.
The default settings as of now are mainly useful for baby shrubs and that’s it, the user is currently required to make some significant changes to the settings if he wants a full-fledged tree with multiple branch levels. It doesn’t have to make a real big tree or a real detailed one, but it should be enough to be a nice starting point.
Second, and this might be a somewhat bigger issue, the algorithm as of now does not space the skinning points in positions that are optimal for good results with the skin modifier, as a result you will have a lot of intersecting/overlapping geometry that need to be cleaned up after the script is run. The skinning points in general need to initially go in a steeper angle away from the intersection before turning because doing that will avoid any perceived quality issues. This can already be cleaned up a bit with the smooth tool, so perhaps adding an option for additional smoothing or displacement could be an option.
Overall, good work, needs some improvements, but it’s in a good position now. Though I do hope we can eventually see some actual skinning functionality in sapling rather than each branch being its own piece (and it’s sometimes not real practical to boolean the branches together though it is faster than trying to manually weld the edges so they can use the skin modifier).