He could grow up to become a super deformed anime character.
Two characters with similar appearances and origins: Alpha the Ultimate Mutant (Defenders #14-15? The issues with Professor X and Magneto circa 1974), and The Futurist (FF #216, 1980). Both are quickly and artificially mutated to cosmic-level super-intelligence and the story ends with them leaving for the stars. And while they both caused a lot of damage and mayhem on their quick road do demigodhood, the point of both stories was that they can’t comfortably be considered “good” or “evil.”
There were Big Head versions of Superman, the Flash and Jimmy Olsen back in the glory days of Julius Schwartz.
The Eterrnals can combine their essences to create the Uni-Mind, basically a giant, golden head.
The Kree Supreme Intelligence
M.O.D.A.M. and all those baby MODOKs…
Big Head and the Brain, from the Ambiguously Gay Duo.
Damn, I always thought it was just his turban that was outsized!
Well, but maybe that’s just because he wears bright colors. Black would have a more slimming effect.