I like this, I was never a fan of having county coaches/directors of cricket being selectors. Their own agenda would too often get in the way.
Getting the opinion of umpires is an option, although I'd prefer asking the county captains their opinion as part of the process (this will most likely happen informally).
No idea who could come in for either the National Selector or Independent England Selector position - they don't necessarily have to know the county game inside out as the new scouts can handle that. Even though Newell and Fraser can apply I don't see them giving up their county roles for the jobs.
All of the candidates I can think of have media contracts that they probably won't give up (Michael Vaughan would be on my shortlist for example).