In terms of wrestling ability; dead last.
In terms of star power; I hate to put John Cena ahead of Bret Hart in anything, but I think Cena trumps Hart in this category. If for nothing else but the longevity of his reign on top. Imo, Cena also trumps the other non-mentioned "faces of the WWE' (Ultimate Warrior, Shawn Michales, Brock Lesner, HHH and any others you consider) in this category. He is far behind Hogan/Rock/Austin though.
I wouldn't say that John Cena would be dead last when it comes to wrestling ability because he is just as good if not better in the ring as The Rock and Hulk Hogan but would be behind Stone Cold Steve Austin who before SummerSlam in 1997 was a great in ring worker and also Bret Hart who is considered one of the best in ring workers ever. As far as great matches from an in ring standpoint i would go as far as to say that John Cena has had better matches than The Rock and Hulk Hogan as well and at 33 years old will only have more.
Also as things stand he is behind Stone Cold Steve Austin, Hulk Hogan and The Rock but what needs to be remembered is that wrestling was so much more popular when those three were around which is what added to their star power and popularity, if any of those would have wrestled from 2005 through to now none would be as HUGE as they are. For John Cena to even be able to get people to ask the question of where he stacks up in comparison shows how big he really is because of where the wrestling industry is now in comparison to back then, as i said above at 33 years old he realistically could be around on top for another decade because there is no one anywhere near him right now.
The biggest names outside of John Cena are Triple H and The Undertaker who are a year or two at most from moving backstage or retiring and after that it would be Rey Mysterio as the nearest to John Cena for star power and he himself is rumoured every year to be retiring because his knees are said to be shot. Next up would be Randy Orton who is so far behind John Cena it is untrue and complete madness when people say that Randy Orton is on the same level as John Cena, then look at everyone else on the roster and tell me a name who looks as if they are honestly going to be bigger than John Cena.
As things stand already John Cena has made more money for WWE through merchandise sales than either of Hulk Hogan or The Rock did and it was reported not long ago that John Cena had actually surpassed Stone Cold Steve Austin as the biggest merchandise seller in wrestling history. John Cena won't have made more money through PPV sales when main eventing as the other three but i wouldn't bet against him doing so because of his longetivity, John Cena has been the main man in WWE for as long as Stone Cold Steve Austin and The Rock's WWE careers lasted and is still going and i'll say it again at 33 years old is still coming towards his prime years.
I'm a HUGE mark for Stone Cold Steve Austin and The Rock and also acknowledge Hulk Hogan as the biggest name to have ever come out of wrestling but people always overlook the fact that whilst they were the biggest names of their era they also had a great mid card and tag team scene as a back up to their main event matches. Look at what John Cena has as back up a lot of the time in comparison to the big three and no matter what anyone says the mid card and tag team scene played a big part in why ratings were so high and why PPV buyrates were doing such HUGE numbers.
In Hulk Hogan's era you had Andre The Giant who was the biggest draw around before Hulk Hogan, Randy Savage, Rowdy Roddy Piper, Ric Flair, The Undertaker, Jake Roberts, The Ultimate Warrior, Ricky Steamboat, Ted DiBiase, The Road Warriors, Demolition, The Hart Foundation, The Rockers, Rick Rude, The British Bulldogs, Sgt Slaughter and Mr Perfect and i know i'm missing some out. Then when Stone Cold Steve Austin and The Rock were around you had The Undertaker, Triple H, Chris Jericho, Chris Benoit, Kurt Angle, Mick Foley, Kane, D-Generation X, Owen Hart, The Road Warriors, The Hardyz, The Dudley Boys, Edge and Christian, Mr McMahon, The Big Show when he mattered and Eddie Guerrero all before WCW and ECW went out of business and WWE got all of their talent as well.
Now no one can deny that all of those wrestlers from that first group contributed a HUGE amount to the ratings and buyrates from when Hulk Hogan was on top and the second group did the same for when Stone Cold Steve Austin and The Rock were on top in their era but then look at the current WWE roster and find someone who honestly draws people into watch outside of John Cena and the old two in Triple H and The Undertaker. I would give anything for WWE to have someone come through to rival John Cena as the main man because that kind if rivalry is good for business and as Stone Cold Steve Austin said having The Rock around brought out the best in each other but John Cena doesn't have that and that will always play a big part in whether he will ever be alongside the big three.