Beautifu l- I've reviewed your all of your suggestions with my non-TE friend. She had seen this at an outdoor show and thought it would be fun. http://www.rocketman.com/products.html
But she doesn't want to pay the big bucks. So a Camelback will have to do.

She has a cabin on Rainy Lake, Ontario - very close to the Minnesota border. Has lots of American friends there and wanted to host a party to remember. I'll tell you how the Camelback worked out in a couple of weeks when she gets back.