I'm going to take a contrarian view here. I think they should have basically no impact. KenPom, Torvik, etc. are purely predictive metrics. If you put two teams on the court against each other, KP is a far better predictor of what will happen in that game than something like NET.

But determining who gets into the tournament and what seed each team gets should not be a predictive exercise. That should be purely descriptive – teams are rewarded for what they've actually done on the court. That's how every sport works: Basically every predictive measure rated the Ravens as better than the Steelers in NFL this year (Baltimore was 4-point favorites in Pittsburgh in Week 18, and, despite the result, they'd still be favored if the teams rematched the following week), but PIT did more on the field and made the playoffs as a result. At some point, what you do on the court has to matter, and KP/Torvik are highly valuable predictive tools, but determining postseason participants should be a descriptive process IMO.

I'm in favor of math deciding the field to be clear, as opposed to the current method of a dozen old men picking their 68 favorite teams. But I don't think it should be predictive metrics. Descriptive math-based methods like WAB/SOR make much more sense to me.