If Puel goes (I'm finding it harder to defend him, and would be utterly unopposed now - and if even I feel like that about a manager he's almost certainly toast), I think that we're probably better planning a proper succession and revamping of the backroom from Rudkin down. This would be better be actioned over the summer, as the best managers and players don't tend to move any other time.
I think there's a lot to be said for the idea of getting in Pearson and Walsh in non-managerial roles that's been suggested (the rest of that idea though...) Of those coaches reguarly seen in the EPL, I would put David Wagner head and shoulders above the rest and he is almost certainly going to be available in the summer. He would also bring a pressing and energetic style which would bring results and be a lot more enjoyable to watch. Of course, there are lots of coaches from further afield who board might be looking into right now - whether that's been Rudkin or Top in the past making those decisions though, I think we have to face up to the fact that they have a pretty poor record of selecting a manager (one Claudio against sacking Pearson the first time, Svenis, Sousa, The Craig and the man who's about to create a vacancy) and should not be asked for a repeat performance. I don't imagine we'll attract one of the very biggest names, so it is possible we'll lose players like Chilwell and Maguire come what mayb but he probably gives us a better chance than most names being mentioned.