Good point. Maybe it's better to get max money out if him now and to have one more transition season and get a proper replacement next summer when one might be available. Though that means we are stuck with overplaying Xavi one more year. And we might have the ban next summer.
Yeah the ban is a problem. I still think Barca will try really hard for a good replacement. IMO they are going to go hard after Koke, even if I do think that won't happen.
However, even when they won't get a clear upgrade, there is still some validity to the notion of selling Cesc for his highest worth right now, as opposed to a year later when he'll likely be worth less, and just finding a player like Rakitic or Ander Herrera, who might not be as talented as Cesc, but will both cost less money than the team will get from the Cesc sale, and would also come with a more defined role, less expectation and consequently less demand, and perhaps a better idea of how their going to be used by the coaching staff and Lucho.