Had a silly shadow of an idea just a few minutes ago.
Well, you all know how Namikaze Minato was- well, a strange person. He was goofy and a bit- flaky outside of combat, but when on a mission, he was laser-focused and could be a killing machine.
Another trait of his was his terrible calligraphy coupled with flawless Sealing skills. I mean, the name 'Kazama Arashi' had to come from somewhere (in-universe), so why not chicken-scratch as the reason?
All of that led me to the idea that Minato had two personalities, one insanely focused, with the ruthlessness and cool-headedness needed on missions. The other- well, a goof, but much more human. Empathy, the ability to connect to people, possibly a tendency to overthink (not as much as Omoi, of course!) and such. The only trait both shared to the highest degree was an attraction to women able to put them in their place and shades of red in their hair, in this AU.
Two personalities: inner Sakura. Could Sakura be Naruto's half-sister? I mean, we know Sakura's parents in canon, but this is a what-if I find funny.
(And please, don't start with the Sakura-hate again...)