Seriously, with NaruHina, it's way too late. We're so far in the manga that there is no way Kishi could possibly do such believably, even if he suddenly decided he wanted to. Hinata has not even had a truly significant appearance since the Chunnin Exams. The "arc" where Team 8tagged along barely showcased any of them, much less Hinata. Add on that there's never been any real attraction, at least on Naruto's end, in over four hundred chapters and I think it's safe to call it dead. Frankly, I'm not sure it was ever really alive.
SasuSaku is just that ship that everyone always seems to love but is also unrealistic and unlikely. I'm convinced by now that the purpose of Sakura's crush was fullfilled, in that she moved on and grew up in a lot of ways. The frivelous crushes were more or less plot devices to advance characters, in both Sakura and Hinata's instances. Hell, Sakura doesn't even seem too sure about the mission to "save" him anymore. Add that she hasn't shown much of anything in the way of real emotion over Sasuke in all of Part 2 and I think it's rather safe to call it dead in the water as well.
NaruSaku has the potential, of course, but it's not really set in stone. In the end, Kishi could decide not to truly make them canon within the series itself and leave such up to the imagination. Or he could decide to go with no pairings at all. It's undecided at this point. But even so, it definitely has a better chance than the other two.
Most of the shippers who actually believe this have little real experience with relationships. It's never clean. People have closer bonds with certain people and fall in love with certain people; no amount of people who think someone else is better for them (usually for shallow reasons) will change that.
It reminds me of the whole deal with the Ramones. Joey Ramone's girlfriend left him for Johnny, which caused a massive rift (and some say inspired the song "The KKK Took My Baby Away"). The two were in love. If she'd stayed with Joey, she and Johnny would have been unhappy. She left and Joey was unhappy and held a grudge.
The words clean and relationship rarely go along in the same sentence. Which is why it's annoying when people ship those two or similar situations in shows for such reasons. It's even more annoying when they ship the other by default, just to pair off both characters of a hated pairing in a different relationship.
I just mean cleaner mathmatically for team 7, I don't mean emotion wise. Everyone gets someone. No one wants anyone to be left out of the Love fest... though it's bound to happen. I feel like a lot of Naruhina and SasuSaku fans just want team 7 to have someone... I really don't believe they're thinking about it enough.