Having serious doubts about KAM already?

No ... how long have you been on this board? I did not want the Vikings to sign Kirk Cousins, but the quarterbacks I liked in the draft were: 

2014 Derek Carr, he was my number one.
2014 Teddy Bridgewater being my number two.
2015 Jameis Winston, but he went number one. I would not have traded away the assets needed to move up. Dodged a bullet.
2016 I didn't look at QBs that offseason. I was focused mainly on WRs.
2017 Patrick Mahomes, the Chiefs paid the price to move up. Mahomes looked good in college, and he had a Minnesota connection with his dad.
2018 Josh Allen, he looked great at the combine. He didn't fall to the Vikings, and he did not look good early on. 
2018 Lamar Jackson, I worried about his picks in college and his passing % needed to be increased, but he fit a modern offense.
2019 I didn't even look at the draft that season until it was over
2020 Justin Herbert, I hoped he would drop, but his quick release was too notable. Vikings got Jefferson, so still a good 1st round.
2021 Mac Jones, slipped to the Vikings spot. The Vikings traded down and picked up Darrisaw at OT.
2022 I didn't look at most positions in the offseason, and QBs were slim anyway.
2023 C. J. Stroud, went way too high for the Vikings to even consider trading up for.

Because I thought they would not go in the top five, I stated the Vikings should target Carr, Allen, Herbert, and Jones. Both Carr and Jones fell to the Vikings pick.

I saw Lamar Jackson as a late first or early second, but if the Vikings had not made the move to sign Cousins, he would have been there for them. Josh Allen was the QB I wanted the Vikings to target, but he went higher than I thought they could trade for.

I thought Mahomes would go top five, so him falling to 10 was an opportunity for some team. Imagine if Spielman was willing to trade up.