Thing is, would Emery take the job? He's in a pretty seat right now. It would represent a fairly big risk for him to leave a successful unfinished project like Villa, and suddenly have the spotlight that comes with the England job.
The first name that springs to mind for me is Jose. He's available, he's known to covet the job, he is a huge step up in tactical acumen, vision, reputation, and probably leadership, and he's great in cup competitions which national football basically consists of.
I wouldn't totally rule out all Englishmen. Eddie Howe is probably the best of the bunch, I wouldn't make him my number one target but again he would be an improvement in class and knowledge. May have the same problems as with Emery though.