Can an argument to the spark profiler command be added something along the lines of --ignore-no-players that doesn't run the profiler when no players are on the server?

I would really like this feature, I hope it gets implemented soon!

You shouldn't be running the profiler for long periods of time and/or unattended anyway, so I don't see a good reason to add this.

spark is most useful when used for short-ish periods of time (1-2 mins) only when you are experiencing a performance issue. Therefore, there is no reason why it should ever be started / running when there are no players on the server.