Well done, Jackie! And, waddya know--a new angle that hasn't been covered before. Thanks for doing this.
I have to disagree in a few places:
--Paul was far more a "legitimate" businessman than his contemporary Dons (as in Joe Colombo as a "realtor"). But, his arrest record and his indictment in the RICO case made him a long-running OC figure. He liked being a businessman (and was good at it), but he was never as obsessed --obsessed--with being considered legitimate as was Michael, or in trying to hide or rationalize his Mafia identity as was Michael. Paul accepted that he was known as a Mafia Don. Michael's obsession with not being known as a Mafia Don defined his life.
--Both distanced themselves fromthe street guys. But, I believe Paul's arrangement with Neil was wary; respectful and arms-length. Michael micromanaged Pentangeli and treated him as a subordinate. I don't think Paul ever gave Neil orders.
--Paul had active arrangements with other Families. Michael wiped out the Dons of the other Families at the end of GF; seemingly had no connections with other OC organizations in II, and in II, seemed to kiss them all goodbye in Atlantic City.
--Tess and Clem weren't passed over--they knew from early on that the Donship would pass from Vito to Sonny, and after Michael returned from Sicily, to him. Tessio's plot against Michael, IMO, was motivated more by Tess's fear that Michael wasn't strong enough to stand up to Barzini than by naked ambition to take over the Corleones.