Depends where you want to base yourself around the city, however Caboolture to the north is a viable alternative to Redcliffe. Quite a few refugees from Archerfield have gone to Boonah to the SW - bit of a drive but a good little country airfield. To the south there is Jacobs Well, however caveat emptor, the resident club is daggers drawn with the landlord, so whilst it will probably survive as an airfield, security of tenure is an issue. All of these are grass or gravel with a mix of GA, RA and gliders. If you're looking for big city facilities with tarmac, only Redcliffe and Archer fit the bill.