Yeah that seems to be the best course of action, especially since Yoshida and co. seem to be trying to make the game more challenging, yet adhere to modern standards. Also that way, they could add decent boss battles without having to redo the entire story, and higher level players would already have access to a string of missions, since they would already be past that point. Looking at the list, there are only 8 total main missions at this point? So they could reduce the rank required for those missions once they add more. Im guessing the lack of main missions is just a remnant of Tanaka's team?
As far as low level NMs go, I remember Yoshi-P stating that they would add a decent amount of low to mid level NMs and content with the next few patches...of course i'd like actual instance (burning circle) battles too, since i'm a sucker for great boss themes/battles, but i'll take what I can get if it means taking down challenging enemies in a party.
It would be nice if the crafting/gathering classes had the combat abilities they were said to have before release, then we wouldnt really have this problem. Either way, i'm really hoping the next two patches are packed with content.