brjones, your concerns about Almora may be right. However...
I remember when the Cubs traded a good young SS, Ivan DeJesus, for a tremendous defensive, aging-SS, Larry Bowa.
And Philadelphia threw in a young guy named Ryne Sandberg. Pretty decent MiLB numbers, a bit better than Almora's but nothing at all eye-popping. The following year he was playing at Wrigley and hadn't shown much power: I remember seeing him hit a VERY long home run and thought, wow, where did that come from? The power didn't show with any consistency for a while, but he got much stronger as he moved through his 20s and was taught how to really turn on the ball by his goofy little manager, Jim Frey...and he adjusted!
Don't want to jinx Almora with a full-on comparison to a HOFer; however, Almora doesn't look at all like the same skinny kid Theo drafted #6...and when Albert squares it up in the air, it's LONG gone! LIke Sandberg, he's a plus defender and has tremendous baseball instincts.
Who knows what Almora's trajectory will be...will he continue to improve his pitch recognition and drive the ball even better as time goes by, as Sandbery certainly did? Impossible to know right now, but I wouldn't put too much stock in his MiLB numbers. Some guys just get bigger and stronger, and develop recognition skills that enable them to hit much better in the majors than minors. Not many adjust really well, but some do.
It's mostly based on my non-expert anecdotal observations (and Theo/Joe's confidence, which is worth a million times more), but I think Almora just might well be one of those guys who becomes a much better hitter at the MLB level as he moves further into his 20s.