McCutchen still seems like the best comp. Most similar body type. Cutch's HR by age:Mookie's #1 comp to me after watching him in 2014 was Gary Sheffield. Watching what he's done in 2015-16 hasn't made me change my mind one bit.
Sheffield hit 33 HR as 23-year old in 1992.
So while it may not be this year, in my mind there are definitely going to be some 30+ HR seasons out there for Mookie. And a 40 HR season shouldn't be taken off the table just yet, either.
Age-HR
22-12
23-16
24-23
25-31
26-21
27-25
28-23