If we are talking about using Suicide the way they did before and having a current member of the Roster under the mask, I have to say that Eric Young is a top candidate. He came back with a more "serious" tone but the beard just comes across as comical. In my opinion, he has to keep it for his Animal Planet show, so what better way to let EY get across that "serious wrestler" attitude than to let him go under the hood. I can see him stretching the run out for a while and making some appearances as just EY to keep things interesting.
If we're talking about putting a new/returning member to the roster under the hood, I can agree that Alex Shelley was the first person to pop in my head; then the name Shawn Daivari popped into my head for some reason. Sheik Abdul Bashir always had a nice way of drawing heat to him and I think if the crowds could get behind the mask of Suicide only then the moment that he took it off (X-belt in hand) and Bashir cracks that smile to the camera could a potentially great TNA moment be created. The only issue I have with this is that there are so many heels in the X-Division as it sits (Kenny King, Zema Ion, Joey Ryan, Garrett Bischoff, Wes Briscoe) but some of the addition of Petey Williams as a face, plus the addition of Sam Shaw (the guy looked much improved on the "Xtravaganza" ONO special), Rockstar Spud, and returning Sorensen should see the division having quite a bit of depth in 2013; now if they add some storylines, the division could be the talk of the town once again and a moment like "Suicide = Bashir" could help create those storylines.