You're probably correct but I still think Walters contract is up in June and if we could offer him a two and a half year deal he may consider it. He'd still play Premier league football up to the Euros.
Ruddy has been dropped and can't get a game ahead of Declan Rudd. Maybe Ruddy could still have hopes of being the third keeper for the England squad and a move here could freshen up his career.
Ledley is an outside bet, but he has a lot of competition at palace, and he will not play much football in the next few years. It depends what type of lad he is , but if he wants to play week in and week out he should relish the chance to step on to the villa park turf as one of Aston Villa's main midfielders.