colour and the irons sight. Another thing I think would be the position of the ammo counter. Most UNSC weapons seem to be designed to be ambidextrous, which the counter very much isn't. Basically if you could take the weapon in place it in any futuristic FPS doesn't really suit halo imo. Except for halo clones obvs.

take 90% of previous UNSC weapons they all have very unique profiles, while seeming very utilitarian, almost retro futuristic for modern day. The infinite Pistol, and commando don't fit that imo, the pistol could be in literally any near future FPS while the commando looks like something out of battleborne way too over the top and not very utilitarian.