After several ottoneu Superflex drafts, I've been interested in how teams have addressed the problem of how many quarterbacks to roster. In both of my leagues, I made a point to draft four starting QBs, but part of my ability to do this stemmed from the fact that many teams drafted only two starters.
My personal feeling is that this is a bit of a strategic error. As @eamuscatuli and I discussed on a recent podcast, it's important to start a QB in your Superflex position, or you risk badly underperforming in head to head matchups. So, even before accounting for injuries, I think it's important to own a third starter to cover your top 2 QBs' bye weeks. Theoretically, this would result in 36 starting QBs owned, and obviously, there are only 32 at any one time, and perhaps 34 or 35 viable starters if you count pairs of players in a true "QB battle" situation. I would expect all of these players to be owned, plus a handful of backups (Dak Prescott is the perfect example of when owning a backup comes in handy).
In both my drafts, several teams drafted just two starting quarterbacks, and some only drafted one. Like I said, I think this is a strategic mistake, not just because they leave their team thin and open to injuries, but because it allows savvy teams to scoop up extra QBs. The ottoneu free agent pool is usually quite thin, and in a Superflex, the QBs available are even thinner, with nearly every viable starter (and then some) owned. While the overall number of QBs owned might seem reasonable, the fact that some teams have stacks of three or four top QBs means that the other teams will have very little recourse if they end up stuck needing to acquire a replacement later on. Unless things start to prove otherwise this year, I'd strongly advise all teams to try and draft three starting QBs in a Superflex draft, and even four if you can manage it. Until most teams start to come around to this strategy, it should be easy to do, so there's no reason to pass up such an advantage.