Without knowing the profile of your source water...
There is really no reason to use anything other than CaCl2 and CaSO4 for calcium. You get the calcium cation without any of the anions that have an affect on pH or flavor unless at high levels. CaOH adds calcium but also raises pH considerably. CaCO3 is insoluble except at quite low pH, so adding it won't add anything to the beer except powdered CaCO3.
I also don't see the point in using MgSO4 in place of, or in addition to, CaSO4 when you're looking to raise the sulfate level.
I use RO on all of my beers.
Can you expound on why not to use MgSO4 in place of CaSO4?
I'm not saying don't use it, I'm saying that I don't see the point in using it. There's nothing that Mg does that Ca doesn't do better. If one is looking to bump up the sulfate a bit, there's no reason not to use CaSO4 to gain the benefits of more Ca. Yes, too much Ca can be detrimental, but so is too much Mg, and everything else for that matter. But I'm not suggesting you dump a kilogram of CaSO4 into your strike water. If, for instance, you want an IPA with 300ppm of SO4, using CaSO4 alone for this will give you ~120ppm of Ca, which is perfectly fine. Why bother with a second salt when one does the trick perfectly well? I don't see any harm in using a little MgSO4 but I also don't see any benefit.
And no disrespect to Kunze, but textbook knowledge and the real world don't always align.