I personally do not see all the angst around creating forums... there has been no proof that it taxes our technical performance. For example, many would eliminate the Religious Travelers Forum for lack of use... but I am guesing that it meets the needs of those who visit... sometimes quality is more important that quantity.
Even different airline/hotel/car forums have different levels of activity and participation.
I see no issue with having more forums...
I would actually have an individual forum for each airline/rental car/hotel program.... vs having the catchall forums.
I hope we do not go down the Reputation route again... we saw how successful that feature was... misused pretty quickly and no longer in place.
William