For presidential elections, I'd vote for 2, 6, and 7. Obviously things are different when you look at the Senate, but for presidential elections I think Republicans are in a lot of trouble demographically going forward, and they really needed to either gain more ground with non-white voters or do better with white voters. Democrats can't count on Republicans having maxed out with rurals and non-college whites, but they have at least some reason to be optimistic that they've stopped the bleeding. And I think any Republican will have a hard time simultaneously appealing to both the Trumpian base and swing voters.
I can’t think of any other point in American history where both parties were within a point of winning the presidency, house, and senate. We’re talking a difference in weather on Election Day margins.
I agree that 2020 was historically unusual, but I think 2000 was similarly close (though I'm not sure just how close the House tipping point race was).
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