Maybe the Harper talent comp is a bit hyperbolic before he's done anything. Or maybe not. One of them has slick SS chops, and the other one is a good corner outfielder. The playing field isn't exactly level. Harper, born in 1992, OPS'd .817 in 2012 and it was borderline other-worldy (considering his age). I really think Profar, born in 1993, could OPS .750 right now, and considering his position I'm pretty sure that would be in nearly the same league of value all things considered.
But I think you gave Bautista an extra year of control there. It's something like (2ish + 4 + 3.5 + 3) for ~50M. If it's 8/WAR then that's like, 50M surplus through 2016.
Profar would crush that. Three league average years at league minimum (probably well below his mean projection for the next 3 years) and he'd already be approaching 50M in surplus value (in the fantastical 8M/WAR paradigm), even before he hits arbitration.