As for the weird tire wear pattern ....
This is called "scalloping" and it's normal if you ride the bike hard. When you corner at higher speeds, the surfaces of the tread blocks experience high lateral forces and are consequently deformed. The tread blocks are pushed sideways, like a pencil eraser when you bear down on it. Tread blocks will get a layer of rubber molecules scrubbed off on a flat plane -- the contact patch -- but they're deformed by the lateral forces. When you park the bike, the tread blocks are no longer under lateral forces, and they relax into their 'normal' state. When relaxed, the scrubbed off surfacec changes from flat (under G-forces) to curved (under no lateral deformation).
That's my understanding, anyway. Seems plausible to me, since I ride like a grandma and rarely see that wear pattern.

Also seems plausible since that wear pattern is uncommon for the rear tire; compared to the lateral forces exerted on the front tire, the rear is just rolling along.