In addition to mileage, what tire pressures are you running?
Is your tire wear question concerning both front and rear tires?
Any saddle bags and/or do you ride two-up often?
Lastly, noting your easy rider comment...is easy riding done at sustained speeds of 75 mph (or more)?
Rear tire in question , front looks almost new and was put on at the same time as the rear. 35#. Mostly empty bags. Ride single. My wgt. about 190#. Down here in the Keys you're pretty much held to 55.
Climate has a major impact on tire mileage. You can ride a lot of miles every year during the coolest weather and see little tread wear. But, those summer miles in Florida will take off the tread. Relax and enjoy the confidence that your tires are sticking tight to that pavement.
I go through my rear tires pretty quick. I almost completely stripped a Maxxis Classic rear in about 7 months, but I ride every day, and several times a day or ALL day in some cases. But, I ride pretty damn hard and I live in AZ where it's hotter than the 7th circle of HELL during the summer...so those could be the two main reasons I go through them so fast.
I'm looking into the Metzlers as well on my next change. They hold up well from what I've heard both on here and from many other people that own them.