The number of people that run games regularly in Ontario can be counter on 2 hands, maybe another foot if you need to. If you chronic problem players, let eachother know.
I suggest those hosts that are having a problem with attendance enforce a non-refundable deposit. If someone is perenially dropping out, make a list, check it twice... let them know they're getting less welcome next time they sign up.
You will accomplish alot more with that, faster and more easily, than with a ratings system that is never going to get made or implemented fully or properly. The KISS principle is in effect.
Whisper_kill pointed out he's already doing some sort of deposit... maybe others should try that approach first if they have concerns about attendance.