Man I dunno, glad someone finally made a thread about this.
Can't wait to start asking moar Wetsuit Elena questions in the next Ask the Devs thread.
If any skin were to return, I would like it to be Wetsuit Elena. However, the reason for her absence is because ND doesn't feel like adding her in the game. Simple as that. I can't believe they'd allow Killzone into Uncharted, but forbid a variation of one of Uncharted's main characters.