Seems a hopeless task TBH, we've only got about 7-8 people who player poker on here and you need 4-5 online at the same time to have a game and it's just been impossible thus far. I'm away for three weeks from friday so I'm ruled out for a while but I can make someone else admin on the pokerstars group if you want to organise something, but I don't hold out much hope.
The main problem as you said is getting people online at the same time. Much harder than I originally imagined.