Probably Hawley
DeSantis has a Quayle comparison
I don't know. He has proven he's very conservative but can "tone it down a little". If Pence doesn't get it, he probably does but he will probably it up the way Rubio did.
If Trump wins, Pence probably gets it unless it goes the way it did with Bush and after everybody got what they can from him and the entire Trump machine is left DOA after the 2022 election.
If the Trump machine is live and kickin' in 2024, Pence gets it. It's as easy as that. Pence doesn't have family or health issues (yet) that would stop him. If Pence doesn't want it, I can see DeSantis, Scott, and Hawley being in the top 3. My money would be on DeSantis.
If Trump get's W'd and all the sudden all of the problems that the "Trump charm" has kept at bay finally show up and he's in the 20s. I think they will be looking at the "next in line" between Rubio and Cruz.
Same if Trump loses. Maybe it would also be open between Haley, Cotton, Cruz, and Rubio.