No, Boruto is alive in the manga. The plot hasn't led to his death. However, the manga is ongoing, and anything could happen in the later developments.
The Akatsuki would surely be affected. They would lose one of their members, which could disrupt their plans. Also, it might change the way other characters view Naruto. Some might see him as a more formidable threat, while others might see him as a hero for taking out a dangerous enemy.
Well, it could happen if Naruto has some sort of special weapon. For example, he might get a sword that can disrupt Hidan's connection with his voodoo - like powers. Once that connection is broken, Naruto could easily defeat and kill Hidan. Also, Naruto's growth in chakra control and strength could play a role. With his enhanced abilities, he could overpower Hidan and deliver a fatal blow.
Well, a 'hidan sakura fanfic' could explore their relationship in a comical way. For example, Hidan accidentally gets a curse that makes him see Sakura as the most important person in the world, and he has to follow her around and protect her while being his usual grumpy self. Or it could be a fanfic set in an alternate universe where Sakura is a ninja assassin like Hidan, and they compete to see who can complete the most difficult assassination missions.
The 'Hidan no Aria' light novel volumes are centered around Kinji and Aria. Kinji is a bit of an enigma with his split - personality - like ability that comes out when he's in a tight spot. Aria, on the other hand, is a top - notch 'Butei' in training. Their relationship starts off a bit rocky but as the story progresses through the volumes, they grow closer while facing numerous threats. There are elements of detective - like investigations as they try to figure out the motives of the bad guys, and also a lot of combat scenes where they show off their skills to survive in the dangerous world of 'Butei'.
Yes, Boruto is indeed a manga. It expands on the Naruto universe and offers fresh perspectives and storylines. Many fans enjoy reading it to delve deeper into the world created by the series.