I think a Winston/Dak is plenty in a 1QB league. Winston has a high ceiling, but Dak is pretty consistent. Rivers is toward the end of his career and in Dynasty, he isn’t going to hold any value really. I’d rather go down and stash a rookie QB if you really do want 3 QBs, but I don’t think it’s necessary. You can ride a Winston/Dak combo for several years. Personally, if I can get a solid QB on a long contract with no pressure to lose the job, I’ll take just them and pick up a guy late late in the draft (or free agency) to play my bye week. Then I’ll keep my eye out for those rookie QBs in later drafts. Like I would potentially draft Murary, Jones, Haskins or Lock in this years rookie draft if I had Rodgers, Ryan or Wilson who’s contracts wont’ be up until 2024.
This way I can stock up on young talent in the RB/WR positions. You never know who will emerge right away and who will take a couple years before they get their shot.