(See inserted corresponding numbers)
1. I didn't mean to insinuate that Luffy should take the majority of the remaining story defeating fodder and avoiding the beasts. I was simply addressing your obvious eagerness for Luffy to defeat a big name in the NW rather quickly after entering the NW, technically but one arc, this past one, ago. He has plenty of build up potential as the story progresses and Oda is beginning what appears to be one of the greatest sagas to date, where Luffy and crew will certainly have a few magical moments I'm sure. Nothing to argue about between the two of us there. I, however, disagree that it will be Luffy to defeat Doflamingo. If Aokiji decides to let him off with a warning or let him escape quietly, the final defeat Doflamingo succumbs to will be at Law's hands, seeing as they have such a history and now vendetta against one another. That or Kaido will actually wipe the floor with him.
2. Yeahhh, I equated defeat with carelessness. Not equal but similar occurences. Either way though, the point I was trying to make is that the crew is still vulnerable, and whatever amount of chapters Oda decides to create do not disregard that each chapter, each villain, power up, etc is all a step in the process of them overcoming the NW. True, the past two arcs conflicts have been relatively easy for the crew to overcome, with a few more pressing struggles I previously mentioned. Again I don't believe we are in mutual agreement that Luffy and crew must face stronger opponents in the future, and ultimately must triumph. But, they have to start somewhere; otherwise, the story risks experiencing those rushed unhyped victories void of the very magic you, I, and everyone who reads One Piece indulges on.
3. Somewhat related to my number two thoughts, number three's matter more so on the idea of the SHs single handedly defeating their enemies from here on out. While the majority certainly will fall by their hands (Shanks, BB, Big Mom), I once again believe Law to be the ultimate benefactor/victor/trump card from this united confrontation against Kaidou, an attack plan based upon the alliance theory which is certain to become more relevant for the duration of the remaining manga. After all, Law explained that this chapter, it is no longer possible for a single crew to eliminate the Yonkou themeselves, let alone their vast underlings. Despite plot biased, Oda cannot simply push a single crew against unrealistic odds he already laid out before us. Face it, alliances are here to stay.
PS. Seems I sort of started the Bleach references going, no? lol