Based on the support for Brisbane, concidering double headers, the Crushers crowds, and those of other codes (in particular the Queensland Reds and Brisbane Lions)....
I would expect they would average somewhere around 26k, similar to what the Queensland Reds get. Not as big as the Broncos admittedly, but sizeable. You would also get a boost to away crowds against the Broncos and Titans.
The big things this bid has going for it will be the:
* expected average crowd numbers, probably around 26,000 mark
* incredable corporate box/support interest, which this bid has already had,
* Suncorp Stadium hosting a game every week,
* Brisbane derby matches,
* huge potential with sponsorships, in Australia's 3rd largest city and
* the large value to the next TV/media deal
ANY bid in Brisbane has this potential, its up to THIS bid to show how it will achieve these things.
You are right, the way they market themselves, the club colours, mascot types of players they recruit, the spirit of the club will be hugely important for this bid to show its strengths.
I guess we won't know how strong this bid is until those details are released (probably around the time of submitting bids). This bid can be unbeatable, but we simply won't know if thats the case until June/July.