Face Regal running for Smackdown GM would be awesome.
I'm not really hyped about this. Like others have said, only a certain segment of the audience will recognise him and he won't get much of a pop. The only way to familiarise him would be to have his past accomplishments and legacy shoved down our thoughts and I'll just end up having even more reasons to hate Michael Cole for things that aren't really his fault, and even then I doubt many people will give a shit honestly.
I mean hell, Road Dogg and Grandmaster Sexay's return pops were non-existent (although Road Dogg's was decent at RR) and they were relevant back in the Attitude Era, Animal even further back.
The angle may be interesting, but it will flop.