A little bit more serious Naruto won't hurt, but I don't want a carbon copy of Minato. And Sakura... I prefer her feisty. More patient... perhaps, but feisty nevertheless! They're still young, so the super adult attitude won't suit them. Naruto acting goofy and Sakura reacting to his quirks... it's their special routine.
I agree that Sakura's feisty behavior is necessary for the comedy routine. But I've always felt that it gets in the way of some tender moments she could share with Naruto. Tender or even just fun. Not a lot of times in the manga, perhaps, but certainly in the movies. Even in RtN, it seemed like they could have shared a much closer experience there if not for Sakura's immature and bold and judgemental behavior.
(I still cringe when I remember that last scene, where they return home and Naruto asks her on a date. Geez, she had such an understanding face at that moment. After all RtN was about her understanding the extent of his loneliness. I thought she would invite him to have dinner with her family. Not in a romantic way even, but to show him support. But she just brushed him off.)
I would like Sakura to conquer her temper a bit and become more considerate and caring on an everyday basis, not giving us this rollercoaster of her being rough and blind all the way to her having the deepest thoughts about her comrades. I know that it would probably look smoother if I were able to adopt the Japaneese point of view, but still...

(The fault, dear Brutus, is not in our stars, but in ourselves, that we are underlings.)