I reckon the final should be at Telstra, but no Australian games in Sydney before that, instead the following wouldn't be a bad idea:
Send one pool game to Newcastle, one and the Aussie semi to Suncorp, then the final pool game to WIN, Canberra, North Qld or perhaps even Melbourne (probably have to be the Aus v NZ game). Sydney crowds will come out for the big final, but I can't see Sydney supporting an Australia v England qualifier at Aussie Stadium in the prelims unfortunately.
Not sure if it is possible for the NZ games to be held over there, if not, spread the rest of the games around the domestic grounds, Parramatta, Aussie, Central Coast, WIN, Newcastle, Campbelltown, Penrith, Canberra, Nth Qld and Gold Coast all have good facilities to run a world cup pool game. I say keep Telstra out of the world cup until the final, and only use Aussie Stadium for games that could get a big crowd, which would be the NZ v England game and thats about it if the Aussie games are played elsewhere.
It comes down to Sydney paying the price for not supporting international rugby league that well in recent times, while Newcastle, Suncorp and even Melbourne had big international crowds.
As for the format, well, I can think of better structures, but at least it gives some quality matches before the semis, both in the 'super' pool and with the other pools not having a team in there that will put 1000 on them. I'd rather see an Ireland v Wales clash that is close and tough than say, Fiji v Australia where we win by 60.