Hey guys been a while, but I just watched a Ready Up Live video
https://www.youtube.com/watch?v=K4ipqE_7fBw about the unknown identity of the "spartan".
He proposed something about it potentially being an A.I., which I know everyone will say sounds stupid, but it got me thinking.
The UNSC has already reverse engineered Forerunner tech (Infinity engines, etc.), what if they reverse engineered the Promethean Knights (keeping in mind they captured that Promethean "soul" in spartan ops) to create new "spartan-bots" so that they're no longer faced with the dilemma of finding volunteers for genetic augmentation, or maybe as a one time special ONI project.
Might be an explanation to the glowing visor, although I'm not really going to advocate my random speculation, just thought it might make for a cool concept.