Another version of your idea 2 would be to use string and support them from your house or a tree. Aerial support sounds like it would need to be very strong, but in a few years of testing it does not seem like the banana trees pull as hard as I imagined. I think that what the support ends up doing is just stopping the plant from blowing down, but otherwise the plant holds itself up.
Since yours are in pots you might have some choices as to where to place the pots to be near a good place to tie up. You'll need some kind of strap to put around each stem, some cheap string to go to the support, and some kind of way to tie to the house without doing damage.
A few pix:
https://picasaweb.google.com/1146855...ortingBunches#
Good luck, I hope you get a bunch from each. Ray