Advice - carry water bottle and side stand plate?

[pekingduck]

Paws, for your sidestand plate, how about a pair of magnetic strips, the kind that have adhesive on one side, attached to the plate, one just on either side of the sidestand foot. That way you could stick it to the sidestand before lowering it, it would tend to stay in place while down, and when you're done, flip the stand up, pull it off and stick it to the rear fender or rack.

As for the water bottle, a bicycle bottle and carrying bracket either attached to the side or underside of the rack may be a start. You might need some of those rubber covered "P" clamps.