Try one of those retractable keyrings.
Velcro does work pretty well.
You can buy a longer hose and quicklink type of attachment, but you'll have to suck harder to get a drink.
Buy the longer insulated hose if you can, then you can shove a spoke down between the neoprene sleeve and the hose, and bend it to shape to bring the mouthpiece up a bit and hold shape.
try flexlinehydration.com they have a nice system w/a check valve. they are good people and should be able to help you out.