Simple suggestion, add the current thread used by the server and also the current bukkit tasks running and bukkit task count.

Maybe in a "/spark threads" command. Just print out all the threads and order by highest utilization. Should be easier than trying to detect which threads the server is using.

It would be useful to detect a CPU thread bottleneck. Especially with a 10s 1m 15m print alongside the tps. And super especially with some sort of (min/med/95%ile/max utilization) print