Unfortunately all actors don't have the option to return to a role, and most of the time it is due to their own personal lives. And their own personal choices. Some actors do not want to get so identified with a persona/character that they are unable to get other roles. (Just tell me how often you see the Walton children, the My 3 Sons boys, the Miami Vice actors, Guiding Light actors (and yes, Daniel Cosgrove - Aiden - was one, but the bigger ones there were Reva Shane, Josh Lewis(Kim Zimmer, Robert Newman) and have not seen them anywhere. You have no idea how much I think Kim Zimmer would bring to Days......oh, boy, to see her go up against Kate would be heaven. Kate needs someone like that.
But to get back to Days.....or any show. Of course we don't like to see a fav pass away, and I know I ramble a bit, but some recasts work well, some do not. When I began watching Days, Bo was played by a recast. No Hope on the show. It was Steve & Kayla that got me watching. Neither liked or disliked Bo at the time. When Philip was recast, I thought the actor did a good job. Many viewers did not. When Shawn D. was recast, not good in my opinion. Belle recast did well, in my opinion. Billie Reed had a couple of recasts........Julie Pinson was superb..again just my opinion. And I could go on......but the fact remains that everyone written off a show cannot be sent to Boston, London, or Chicago.
We still get Chloe back, Melanie, Philip, Belle, ShawnD, and countless others who may be residing elsewhere, but are still alive.