Condo Rental Waitlist Ideas?

I am new to the site and open to idea from other HOA board members/Condo owners who have faced issues with their condo rental waitlists, especially regarding waitlists that simply are not moving. Currently, our 17 unit building has a cap of 5 units that can be rented (rental restriction are in our bylaws). Several us these rented out units have been leased for several years at this point, making our rental waitlist stagnate and frustration other owners who want to rent their units. These owners feel it is unfair to allow units to be rented for years and years without penalties or restrictions.

We currently have several restrictions in place: seasoning clause, 1 year minimum lease agreements, and rental fees paid by owners. Any ideas on how to keep the waitlist moving? Or, is it positive that units are regularly restricted from being rented out? Any help is appreciated!