It really doesn't though if you go back and re-read the whole series there's seriously hints to it actually being more than the gum gum fruit. If you look into mythology he's very similarly based to Wukong who by the way is a sun god and has complete control over his body and what he can look like, as well as stretch with elasticity, just like Luffy

Kai and Zamasu aren't immortal. They do have longer lives than mortals, Zamasu specifically asked Super Shenron for immortality, hence why when his body is destroyed he becomes that universe

Partly correctVaraMahiesedotter the OG FMA aired in 2004 which is the one that got too far ahead of the manga so they created their own ending. FMA Brotherhood which follows the story faithfully to the manga aired in 2010

Peak Dabura would've been controlled + the third eye obviously. But the third eye thing didn't exist originally so you're original statement is correct. But with the third eye retcon it isn't correct