Yep, CM Punk has now joined the likes of HHH, Cena, Orton, Mysterio, Jericho et al in that he's won most of the titles in WWE. What's he still got to accomplish? If I were him I'd want actual bona fide main events at PPVs. I'd want my name at the top of the bill, my face on collectors cups and down the side of buses. I'd want my name to become recognizable in the way the Hulk Hogan, Stone Cold and The Rock are.
My Mum knows who Hulk Hogan is. My Ex knows who The Rock and Stone Cold are. Neither have the slightest interest in wrestling or WWE otherwise and neither have any clue who CM Punk is. Personally I don't think Cena has reached that level of international cross-over recognition but if I were in WWE that's what I'd want and I assume 90% of the roster would agree.
There's always more to do in wrestling, there's always someone new to be, some legend to challenge, one more grand stage to headline. For me Punk should be looking at headlining a Wrestlemania, winning the Royal Rumble, fighting Stone Cold and/or The Undertaker at Wrestlemania. Of course he might just agree with Great One and retire when he gets bored, who knows?