My problem with updating the template like your mentioning is the provision process was based of the snapvol.cfg and the template you started with. It excluded certain things, and when you update the under lying template that stuff is still missing anyway. The only time I've remade app stacks has been going from window 7 to windows 10. Outside of that if they still work then I won't change the template or anything. I've gone from 2.6 to 2.13 and this has worked for me so far.
Thanks, sjesse. That's the answer that I was hoping for.