But then again, it depends a lot on the own personal views on romance.
Personally I love the amount of romance Kishi put in it, because it is sparsely enough to not distract from the main plot lines, but always subtle enough there to keep things going. Honestly, without any pairing bias, the only thing that went totally wrong was Sakura's for love for Sasuke - because we simply don't see it in a way, to make us grasp it.
NS and NH were handled okayish, although it didn't go at the end like I personally would have wanted it.^^ It made at least sense.
Of course not to mention that an NS route during the last third/fourth of the Manga would have been sooo much better in every aspect (+ Sakura focus like you wrote) , but well, you can't have everything, can you?
The Last is a nice movie; the romance in Naruto was more important than in other series', so it was clear that it had to be addressed somehow at the end, no matter how (In the last chapters or a extra movie like here), or which pairing happened.
The movie did this job, but it had many poor aspects:
-Too much focus on romance, what made the movie feel extremely awkward.
-NH was built up during the last parts of the manga; the movie ignored too much of what was written in the Manga, and makes Naruto look like an total idiot.
Which in reverse makes his love for Hinata look ridiculous.
-Other inconsistencies.
-And of course for us: How NS was handled.
It's not totally bad, with great. allusions to the fake confession scene; but all in all not satisfying enough. Like the things that were implicated, or that it felt like there were things in the air, that weren't talked about.
-Too much unresolved points.
To sum it up:
I don't think The Last is there to 'justify' NH or something like that, enough of it was already there in the Manga; the movie is pure fan-service.
But it is a bad movie in it's core aspect, the romance and doesn't the much else beside romance, which is extremely disappointing for 'the last' movie.