Advice - carry water bottle and side stand plate?

[Papa Weeley_imp]

Sounds like a Camelback or similar hydration pack is perfect for you. They're extremely slim and comfortable, and most have some storage area that something like a sidestand puck would easily fit into. I've got a couple of friends that swear by them.
As for sidestand supports, I've been using the same one for years from my Ducati days that fits flat in any of my jacket pockets - still looks brand new, and works great:

[url=http://s157.photobucket.com/user/mustangfeverrr/media/2015-10-16%20034_zps3kd0a4g5.jpg.html]