Agree with this mainly.
Over a period of 2-3 years everyone needs to be playing the same amount of tests. Sadly I think the horse has already bolted because of all the smaller format competitions and tours these days
Copious ODI and T20 tours.
IPL
SA20
Big Bash
CPL
The godforsaken Hundred.
That's where the money is for the most part.
As much as we all love Test Cricket and it keeps producing some strategically formidable contests, it's just not as attractive any more for the main. Sadly.
I don't even want to see India vs Aus each year (especially after this latest series!). But that's where it gets too saturated. Instead of having different points won compared to the nation you're playing, maybe have bigger nations play more away tests so they're not always given the advantage of home crowds/surfaces. And relegation can happen to anyone.