I'd love for Naruto to think of what Itachi told him about Minato succeeding because he had Kushina by his side to support him, and apply it to Sakura being by his side.
Yeah, I think this would be great development if Kishi did it this way. My opinion at this point is that the love subplot wont be completely resolved until after Sasuke is redeemed, but that there is a good chance of more hints being thrown in before that moment. I'd love it if Naruto and Sakura talked beforehand.

To me, it made the POAL less important to the story as a whole than I had originally interpreted. No longer is Sasuke being saved truly tied in with it. It is now entirely an action of love towards Sakura. Which is fine, it stands as the most romantic part of the story. He was giving up his chance with her, essentially, because of his selfless love. However, I always considered it might have given him an extra incentive or push to fight harder. He did reflect on Sakura during the VotE fight. I don't think now you can say he is facing Sasuke with Sakura's feelings in mind since she basically told him not to.
That's why I feel Kishi demeaned it somewhat, and why I don't necessarily see its place in the story as big as it was. Though, it is true Naruto himself did not say anything that indicated his feelings had changed. I'm looking more at the way Kishi handled bringing it back into the story like he did. And, from what Sakura understood of the promise, I'm glad she wanted to remove that burden (even though she did not fully understand the true point of his words).
All in all, I don't feel it a threat if the POAL is lessened in any way when it comes to Sasuke. The main point was always that it showed how selfless Naruto's love is for her. As long as Sakura reflects on that point, I don't think it matters if the POAL is put to rest. And also, like people have said, it might pave the way for equally adamant promises between them rather than just a one-sided one. The POAL is nice and all for the development at the time, but I'd rather them start to be honest with one another so they didn't have to make these sacrifices of love.