To me, there's more to being a legend than just playing well for years.
Real legends have that something extra personality wise.
Kenny is a Legend for what he did back both on the pitch and off.
Barnes is a Legend for what he endured and his continuing loyalty to the club.
Rafa is a Legend for all that he did.
With this in mind, I'm thinking of players that seem to make a connection with the fans. In the modern squad. Pepe, Luis, Jamie, Jay Spearing, Lucas, Daniel, and Dirk all seem to have this at the moment. Stevie to a lesser degree because he only really shows any personality on the pitch.
But of course talent and longevity are vital parts of this too.
Of players that had the touch of madness but also seemed Red through and through,
Who had the talent (or at least appeared to),
and who join early enough that they could have played for us for years:
Ryan Babel - seemed to have bags of talent. was outspoken but sound. was a bit bonkers. (For one reason or another, his development stalled and he was inconsistant)
Djibril Cissé - Had bags of speed, seemed like he was a top striker, was a crazy as a mansion full of frog. (Never managed to turn his speed and shooting skills into the world beater he could have been)
Raul Meireles - loads of talent, seemed devoted to the cause, looked like some crazed gay biker on acid (But turned out to be a bit of snake)
Stephen Warnock - looked for a while as if he might be the answer at left back, local lad, took no prisoners (but sadly didn't quite develop enough)
Oh, and of course Torres who could have had it all.