I think that's a possible plan. Of course, it's very possible that one is gone by #3. Is the other worth the #3 pick at this point in his development?
I've heard conflicting reports on both, so to me, unless you think one of them will become a better QB than Mayfield, that probably should be the plan. Before you say "yes!" to that, go and look at Mayfield's draft profile. He's matured and seasoned now and showing some of that college swagger at the next level.
My personal opinion is that the Pats are a lot closer to getting back in the hunt than most here. They need a QB, a left tackle, a top TE, and a couple of WRs, but beyond that, they're pretty damned solid. And they can solve two of those with the draft, hopefully, which is deep in WR and LT. And Fa should get them the TE they need and the other pieces, perhaps including QB.
Again, if the Pats think THE NEXT GUY will be there for them, take him, sure. If not, the opportunity to get a QB of Mayfield's quality (top 15) doesn't come around much. I really don't want to be having these conversations after another 3 years of the last 3 years.