After reading more and watching more on Burrow and Tagovailoa (including full games--quarantine gets boring), I'm still convinced that Tagovailoa is the superior talent, though not by a lot. With Burrow having significantly less health concern, he's a perfectly defensible choice as #1.
Tagovailoa looks to me like Andrew Luck with not quite as strong an arm. It's plenty strong enough, but Luck had a stronger one. Everything else, the really important stuff, is the same--brilliant, quick processing and decision-making, fantastic accuracy to every level of the field, sharp and consistent footwork and mechanics, high level anticipation, compact release and sneaky good athleticism. Tagovailoa may not be straight-line fast, but he's extremely nimble in the pocket and elusive enough to make people miss in the open field. He won't make any 60-yard touchdown runs like Randall Cunningham, Michael Vick or Colin Kaepernick, but he'll easily rip off 10-15 yard runs for first downs when nothing's available and the defense loses contain. Which is enough to kill defenses when combined with his tremendous passing. More often, he'll simply avoid a sack and make a play with his arm.
Joe Burrow reminds me of a poor man's Aaron Rodgers, oddly enough. "Poor man's" because he's not nearly as athletic as Rodgers, nor does he have nearly as big of an arm. But what he does have, which reminds me a ton of Rodgers, is the improvisational ability and the mentality of a gunslinger without the turnovers. Those two things are always what typified Rodgers to me. The confidence and ability to make difficult throws (i.e. what makes a "gunslinger" in my opinion) is not that uncommon--but usually those types of players commit a lot of turnovers in the process. In fact, if you want to compare Rodgers and Brett Favre, both were gunslingers, both were great at improvisation. But what separated Rodgers was that he did it without all the interceptions. I see the same thing from Burrow--he makes a ton of high degree of difficulty throws, but his gambles pay off more often than not, and when they don't, he doesn't end up putting the ball in harm's way. He knows how to attempt improbable throws in a way where either his receiver gets it, or no one does. And the consistency with which he puts these "spinning out of a sack, dodging another would-be-tackler and firing the ball 40 yards downfield while falling out of bounds" throws right on his receiver was what was so stunning about his 2019 season.
If (and obviously it's a huge "if") Tagovailoa is healthy, I'd rather have him. He not only played at an exceptional level longer, he's as can't-miss (again, on talent, disregarding health) as any quarterback prospect I've seen, because he does everything so well technically and understands and processes the game at such a high level. But both prospects are outstanding.
Where pundits (and NFL GMs, if reports are to be believed) lose me is when they start pushing Herbert or Love ahead of Tagovailoa. Even when you factor in injury risk, it's absurd to draft either of those two ahead of Tagovailoa. Herbert is your average first-round quarterback prospect--potentially quite good, but nothing that screams special--and Love is your average second-round lottery ticket who might be elevated into the first round by a desperate team. Even with the risk that Tagovailoa flames out because of injury, he still represents a much better chance at a superstar, franchise quarterback because he comes into the league as nearly a ready-made one. He just has to dodge the injury bullet. Herbert doesn't have superstar talent and Love is the kind of prospect where if you hit the 5% chance that everything clicks, you could have a star quarterback. If it goes the other way, you have an athlete who's a mediocre quarterback.
