VFL is miles ahead at the moment, due to TAC players who miss out on AFL selection going to VFL Clubs.
Problem you have with both SAFL and WAFL is that players who fall out of the AFL system go back to these comps, example being T. Roach, Jesse Smith etc.
saying that I havent seen and SAFL or WAFL game live for 4 years now, so things might have changed
Also Vic Footy Suburban Footy pays good money, so that players who also have been involved in AFL go back there and get great $$$$ a game, on par with SA footy eg Patrick Bowden, Troy Simmonds, Kane Johnson, Brodie Holland, Ben Haynes, Scott Lucas, Luke Livingston, etc