There are plenty of, to borrow a Bowman-ism, reasons to believe that Kemp will hit next year. In the first half last year his BABIP was .285 which was probably at least 30 points lower than it should have been. So he did have a little bad luck. However, in the second half his BABIP was .315, a completely sustainable number. One below his career norm actually (.340 for his career). So it's not like Kemp's second half .906 OPS was entirely luck based.
I agree that an .850 OPS this year isn't a reach at all. It's perfectly reasonable.
Also, I think the defensive stuff is overblown. If he were in right or center he'd be a huge liability. But we can take that hit in left.
Do hits in left count less than hits in right?