I no longer 'run' a club , but when I was running Uxbridge back then , we had a singers night to start the month , and a Major Guest to finish the month , with the evenings in between (A Weekly Club ) we were booking less expensive local and up and coming performers .
The Floor spots were usually three songs , with preference given to singers we did not see on a regular basis - The regular singers , those who attended most weeks knew that visiting singers would be used , so the locals were happy to stand down if there were too many floor spots .
It worked very well for several years , till I gave up as Boss Man .