As far as "rising stars" that might be major players in 2024, one really sticks out in my mind: Missouri Governor Eric Greitans. If he's reelected in 2020, then 2024 will coincidence with the end of his second-term as governor - perfect timing for a Presidential run. He'll be relatively young (only 50 in 2024), he's unabashedly conservative, Jewish, a former Navy SEAL and Rhodes Scholar, and (based on what I've seen so far) might be the perfect Republican to bridge the South/Midwest and Trump/religious right divides. He's all the advantages of Pence x10, plus youth, without the Trump baggage.
The only way this guy isn't a GOP nominee one day is through some sort of major self-inflicted wound.
if he only knew