I have to say, I don't get a lot out of the Smoker/Tashigi thing, they're just a little too mentor/protege for me to see anything beyond that being very feasible. She's like Luke to his Obi-Wan, only if Obi-Wan never wore a shirt, chain-smoked huge cigars and told Luke to stop messing around with the light sabers and pay attention more often. I think there's a great deal of mutual respect between them, but I just don't see any potential romantic stuff. That's just my opinion.
Smoker/Hina, on the other hand, I could see having some potential, they've got that whole 'bickering like a married couple' dynamic going on.
And I swear, I must be the only person in the world that didn't see Luffy putting his hat on Nami as something romantic. I saw it as an act of true friendship, that he didn't have a clue what was going on but it didn't matter, and no matter what she'd done or said to them previously, they were still nakama and they'd help her. I don't think he'd have done anything less for any of the rest of them, quite frankly, and that's the thing I love about Luffy, all his nakama are equal, no one is more special to him than anyone else.
–Bevin