ouch, it's too bad, I was in for this one.
I hear you Stu, it is a lot of work and then it sucks to have no one show up.
Maybe it's cuz we are in the middle of a league and most people are probably practicing the league tracks with their spare time instead of joining some club races. Which is too bad, cuz the club races are so much fun!
Maybe you could pick just one car (or group, like just TC-65 or just something like that), one track, and one race for the club races and keep the races around 14 to 16 laps. That way the folks that are spending a lot of their time practicing won't see it as a big time commitment for them to join the club races.
And as an added bonus, you end up spending less time into the setting up, since it's just one car or group and track.
This is just me thinking out loud cuz I do enjoy the club races very much, more so than the league races cuz there is less pressure to win.