I don’t even know where to begin.
1) How is Kepler not consistent compared with Buxton and Sano? His three years at the MLB level he posted OPS + of 96, 95 and 96. That’s the literal definition of consistent.
2) Why does he have to prove he can consistently hit? Buxton and Sano sure as hell haven’t.
3) IMO Kepler is more likely to be a Twin in 5 years than Sano or Buxton. Or Rosario frankly.
Kepler is 26. You can begin there.