I'm liking this O'Shea as OC idea. Don't need a QB coach, as O'Shea and Richt Sr. will do that, as both are former college QBs. Let O'Shea bring in his own O-line coach. Someone he believes could best coach his offensive system. Maybe someone from the NFL, so that UM coaches can at least make the "I know how to turn you into an NFL lineman" pitch to the big nasties (or maybe someone good enough who could convincingly say "I can make anyone into an NFL lineman"). Keep Duggans, and O'Shea will be there to help.
I have no idea how much he would cost.
Would be nice to have someone from the NFL leading the offense, someone who has a lot of experience having to analyze opposing defenses to find weaknesses, and creating plays and schemes to exploit those, and installing those plays in 2-3 days each week, rather than just lining up and running the same 10-15 plays you always run, hoping that they work. UM isn't going to get an NFL OC, but it could get an upper level assistant like O'Shea or someone similar from another high powered offense. It would need to be someone with some college experience so they know how to recruit. O'Shea has that. He was also a HS head coach for about 5 years, so he can probably relate to 16, 17 and 18 year old kids he would be forced schmooze for recruiting purposes. UM can't hire a Kool type who is on paper an excellent coach but can't recruit.