Are we sailing down da Nile here?
I think that Rick will die. If they are going to lose their leading character and basically have to reboot the series, surely they would want to make it an huge event. Rick running off on a side quest, going to some far community or just disappearing is not really epic. I anticipate a heroic or at least game changing death for Rick and that Michonne will lead Alexandria and raise Judith for as long as DG wants to stay with TWD.
Also, why leave the fans hanging, again? Lincoln has hinted a few times over the years that Rick might not make it. He wants out, he wants to go back to England and the way out on TWD is death. We don't need another lost character. There is or was more than enough speculation about Heath, Morales and Beth.
On the other hand, I think that Maggie will take Hershel and move to Georgie's community for some unknown reason, leaving the door open to her coming back. That's been fairly obviously foreshadowed.