This gimmick wouldn't have worked in the heyday of Max Moon, let alone now.
Look at the current storylines in the WWE. Since WrestleMania, we've had the big CM Punk vs John Cena feud, the Triple H COO storyline, and the Cena/Rock feud, for example. Punk vs Cena was based around contracts, money, fame, power. Triple H's COO storyline was based around...contracts, money, fame, and power. The Cena/Rock storyline? A little different, but at the end of the day there's no real gimmick to it. Rocky has transcended any sort of gimmick, he's just the Rock, and Cena is much the same. They're just two mega stars clashing.
Let's face facts, folks - the era of these kinds of gimmicks is dead. Want proof that they don't work in today's WWE? How about Kizarny? Who? Right, the utter failure of a creepy clown guy who nobody bought into because the gimmick doesn't gel with modern WWE. (Disclaimer: Despite Kizarny failing miserably in the WWE, Sinn Bodhi is currently being awesome on the indy circuit, particularly in CHIKARA, where these things are still alive and well). Remember Hurricane Helms? Sure, he kind of worked in the goofiness of the Attitude Era (when, you'll note, this sort of thing was beginning its death knell). Then they tried to bring it back in the ECW reboot. Fell flat on its face. DJ Gabriel? Yeah, I don't even need to explain that one.
Admittedly, Skip Sheffield has something that sets him apart from all of these guys -the fact that he's a behemoth, which helps a lot in the WWE. But pretending he's a terminator from the future? Come on, guys. Just think about how well that would go over. Read: it wouldn't. I'm fine with calling him Ryback, if we must. I'm fine with giving him some personality, goodness knows he needs it. But there's a huge difference between personality and such an over the top gimmick as this.
Note how the most successful guys in the WWE got to where they are today. Punk played the straightedge card to great success on his way to the top. But he wasn't a DARE Officer, or a prohibitionist, or something silly like that. It was an aspect of his overall personality. At the end of the day he was a real person - like everyone else. A lot of people might say that this is boring, or something. It isn't, it's the natural progression of the WWE. There's plenty of other places to get your fill on gimmick heavy product. Watch CHIKARA. The modern WWE superstar doesn't have a gimmick - he has a personality, which is entirely different. Ryback, terminator from the future? That's a gimmick, and it will fail if they push it too hard down the Robocop lane. Find some kind of balance. Call him Ryback if you must, but perhaps he's a justice obsessed, avenger type who straddles the line of face and heel. Now that's an intriguing personality for any modern WWE star.
Finally, in closing, note that there are obvious exceptions for the Undertaker and to a lesser extent Kane who have achieved a sort of transcendence from all this. But at the end of the day it ought to be quite obvious that no heavy gimmick will succeed in the WWE today. One requires a personality, not a gimmick. Bring in Ryback, the Man From the Future...and he'll be on his way to future endeavors.