RE: Ordered bow with wrong draw weight.
Go ahead and order your new limbs to achieve the draw weight you want.
Most of the guys on this website that have 9000+ years of experience and have shoulder injuries speak of staying with a lower poundage bow. What you need to learn from these guys is that most of them are injuried because they never learned the proper way to pull back a higher poundage bow or....they went beyond what felt comfortable and did not listen to what their bodies were telling them. If you can pull it properly and comfortably, then shoot it!
I agree with whoever said a 60lb bow feels like a toy. I know for my personal use, I lock into my form better with a higher poundage drawing bow.
I agree with Dave, I would want the higher KE if a good shot goes bad. It almost boils down to an ethical issue. Do I want a bow that puts an arrow 6" into the foam block or a bow that puts an arrow 10" into the foam block. Think what happens if that foam block becomes a deers shoulder.
As for the comment saying that a 60lb bow will take down anything on this continent....well...so will a .22 rifle. But do people hunt elk and caribbou with a .22 rifle? I should hope not. A .22 rifle is not as effective (range and knock down power) as a .30-06. Same thing with a 60lb bow IMO.
It's funny,I never hear of people saying...you should be shooting a 70lb bow instead of a 60lb bow. Yet you quite often hear the reverse. It's almost amusing at times.