I didn't see the point in in the different marine skins, they all look the exact same to me, just different heads, and that's barely noticeable when playing MP. I would have loved to see some diversity, such as a character in pilot gear, a smart gunner vest, ect. Even a female marine would have been appreciated.
Considering that Tequila was such as secondary character, the pretty much the only other marine you're around long enough to have any impact, I'm amazed she's not a skin in MP.