Whether or not the leaf decay rate is set to 100 or 1,000, leaves seem to decay at a default rate.

Also, the decay rate seems to slow down exponentially as fewer and fewer leaves are left, leaving single block leaves hanging in the air for several minutes.

this way would be too heavy. However, you can activate the greedy leaf removal, this will speed up the decay and clear leaves that are not close to logs

Please try the new version 4.0 and let me know if that works better for you.

What about finding and removing leaves that are >= 3 or 4 blocks away from a log, and are also not player-placed?

No idea if this'll work. Just a suggestion.

Seems to be much better, but I'm still noticing smaller clumps of leaves are untouched longer than large clumps.

As the leaves decay in big clumps, it leaves smaller ones, and the small ones tend to stay in the air longer. Regardless, this is indeed better.

Curious, if your plugin was installed on a server with leaves that haven't decayed yet, would your plugin find them (when the chunk is loaded) and decay them quickly? I know of a few servers with hanging leaves that could find this very useful to pretty things up.

Yeah what I'm doing (as its very non-resource heavy) is just removing a 3x3 leaf block around any leaf that naturally decay's. I haven't had the time to run through and figure out how to track which tree a leaf is attacked to yet.

And yes, it would work on leaves that haven't decayed yet.

I will find a way to find those hanging last leaf blocks.