My advice and what I'd do if I were in your shoes is flower both! You have a nice choice of opposites so why not have a stash for almost any need? I would never allow my stash to be without at least several varieties/strains to chose from, and it also helps prevent tolerance build-up. The Afghan is the base strain for blueberry and many other indica hybrids and should finish a couple weeks sooner than the NL too, if that helps with your decision.

Good luck with the flowering and hope to see some pics!