I think their numbers are okay when they doing well, much like Brisbane and Sydney do. We really haven't seen a major drought for Adelaide or West Coast. Their attendance has dropped a bit despite a membership queue, don't know how well they would do with a long drought. Freo has been very solid of late despite no real success.
I don't think they overcharge in SA, like they do in WA, so I think Crows would feel a support drop a lot more than they would in the west.
I think the inherit weakness of Port vs Crows is that Port represents one SA team while Crows represent everyone else. If they were to change name to South Australian Power and make more of an emphasis to represent all their feeder clubs then over time they would probably get a lot more support from the other supporter bases than they presently get.
I don't think Port Adelaide supporters would like that, it would diminish the club in terms of being the Port Adelaide Magpies entry into the AFL but it would significantly broaden their supporter base.
They wouldn't accept that at all - and I wouldn't blame them really. If you changed their name to Adelaide Power, even if based at Alberton and keeping colours, logo etc their fans would drop off in droves, chicken poo would be dumped on the doorstep AND no neutral would fall for it and support them. So then you'd have a white elephant. If you were to do that you may as well move them to Tassie because they would have nothing here. The broader SA community would STILL think of them as Port.
They wouldn't do well with a long drought, they'd do it tough, their supporters aren't used to that and would react.