Despite his confidence knock, if I was a team like Celtic or Newcastle I would love Moyes at the helm.
Sure Moyes didn't suit Man United, but My Cashley's (ba-dum-tss) stingey with money, which is something that Moyes doesn't really use efficiently in large sums, in that case Moyes going to Newcastle justifies Ashley not giving him loads, meanwhile Moyes can make Newcastle a consistent European team(Europa League).
Moyes should take Guardiola style sabbatical, come back and see his options though, and if there's a job he wants at that time, he should go for it, I just really hope teams don't do what the media/people are doing; Insinutating Moyes would be terrible where ever he goes next (If anywhere), considering what he did for Everton.