Iunno. I think having the normal mode be story-only would be a waste. The game needs more mid-tier content, imo, and having normal drop loot would be a good way to do it.

Normal could be of a difficulty similar to EX Primals- not too hard, and pretty doable once everyone has the hang of things. Still requiring cohesion and teamwork, but not to the extent that FCoB currently demands. It would drop lower item level equipment (probably the same level as currency gear, if that system is kept) and said items would probably look different compared to HM drops, similar to the visual differences between i100 and i110 PvP gear. (yay, glamour options!) A lockout would still be in place, of course.

Hard mode difficulty would be akin to the current raid, or tuned slightly higher (due to the availability of NM gear.) It would feature new and deeper mechanics than normal, some of which are entirely different, to keep things exciting and surprising.