O&A didn't need a third mic. I was always in favor of the stations dumping Norton, or reducing him to a weekly guest. I wasn't listening to the show to hear about his juicy BBC penis obsessions and other various perversions. I was trying to listen to Opie & Anthony and this faggot got in the way.
With O&A you only made for good radio if you were willing to always sink lower than them, and throw more fuel to the fire.
Bobby was just enough like Norton that it would have worked, and without Norton's irritating quirks... Bobby's stupid quirks aren't malicious. He's like an abused dog that just wants approval. He still has dumb molestation stories, bald pixar animation appearance, violent fantasies, etc. The only thing Norton has on Bobby is he's got no limits. He was willing to roll with anything. At times Bobby was speechless or jokingly offended (like Benoit) and then he doesn't know what to contribute. Bobby would have softened the show's tone a tad.
Part of the reason why Norton did fit into his role was also that he was just as uninformed and retarded as O&A. He was constantly out of the loop and asking stupid ass questions which was amusing to hear them kick around things that most people my age think of with reverence. O&A misunderstand and try to fathom basic pop culture trends was like live action Beavis & Butthead, but you can't write the shit they would come up with.
The truth is Patrice was a hit or miss listen when you were a live listener at the time. I would generally skip the live show and wait for the replay to see if it was a Patrice episode worth skipping around or not. Revisionist history says everyone loved Patrice. I can listen to Patrice rant for hours, but only because its by choice. Sometimes you just don't need to listen to Patrice Oneal at 7 in the morning. You want a normal O&A show and it's bad enough Norton was usually there to shit things up.
Kevin Hart also would have been better than Patrice, Norton, or Bobby. I'm surprised Kevin Hart hasn't used Bob Kelly in some fashion, they could have one of those Obama/Biden BFF reddit memes going together. But why do that when Kevin is trying to date upwards with The Rock.
Bill Burr added an interesting dynamic to O&A moreso than the others, and more similar to what Louis CK would often bring out of them. You could tell by the way Burr and Louis interacted with O&A that they were smart businessmen who were going to go farther than the others... Yes they were participating in the show, but even during their appearances it felt like they were constantly commenting on and analyzing the concept of what O&A did, rather than just stupidly following them, like a Lewis Black. Patrice would just blather for hours about his movie observations. Louis and Burr would let the show happen and then talk about why it was brilliant. Burr still goes on Rogan to talk about O&A despite everything else.
Brian Regan would have been better than Bill Burr. Regan would floor the entire studio at WNEW just by acting like a retard without cursing or saying anything even remotely offensive to anyone. That would have probably been the best case scenario for O&A... Regan still never ended up being a huge mainstream star even though he was hilarious and had it all. O&A would have been a good boost for him, but I don't know where he lived at the time. Probably didn't want to move his wife and kids around.
Jay Mohr was like the white Patrice. He always tends to crash the show and just go on about himself, which is fine because it means they have material. But after a few minutes it becomes clear "This is a Jay Mohr episode" and sometimes you just don't feel like listening to his shit either for 3 hours.
I never really tuned into Florentine episodes because my girlfriend at the time despised Florentine and all the hosts from the VH1 Metal Show that he was on, so I would just turn it off to avoid her sperg rage which was hilarious to witness but not while driving. But whenever I hear Florentine on O&A it's some episode where you find out he's there in the middle of the segment when he has some random comment or someone asks him something. Which is ideal for a third mic, but he never really delivers. Otto & George were great in their first few appearances until Otto started just being a panelist who never said anything.
I don't think Vos had the energy in later years to be third mic. He was like a tired old boxer who started losing fights late in his career. Vos basically raised O&A to be successful in New York. He beat the hack out of them, and then started bringing guys like Patrice who would carry on that roasting shit that everyone loved.
At the end of the day, the only true answer is the impossible answer that never could happen ... Colin Quinn. He personified all the positive qualities of everyone I just described, with almost none of the negatives. Colin would always roll with the show, when necessary he wouldn't say a peep, and whenever he did say something it was usually a death blow to someone, even to the show itself at times. Norton stole from CQ the most out of anyone, so it would follow that CQ would have been the most beneficial for the role. The sad fact is that he was too lazy and non-commital to even do a low effort phone podcast with his 280 lb friend, or a radio show with Nick Dipalo, or a movie with Mike Meyers, etc.
I wonder how Artie Lange in his prime would have complemented O&A... Norton became the official third mic around the same time Artie became Stern's third mic. If those roles were reversed, Norton would have lasted a few months before Stern got sick of him being lazy and not paying attention. Norton wouldn't like being treated like a Wack Packer but he probably would have done it for the road money.