You are certainly correct in that there are plenty of opportunities for even the experienced to be confused when it comes to water chemistry but, fortunately, this isn't one of them. It represents an excellent example of the case for KISS in brewing and I always recommend that people just starting out try to keep things as simple as possible. Believe me, there will be plenty of opportunities to experience the not so simple.
Basically an all grain mash needs a little chloride in the water and a little acid. A bit of calcium doesn't hurt and as you need something to pair the chloride with and calcium chloride is a common, readily available salt calcium is often taken care of automatically. You can make a good beer of almost any style with a little calcium chloride and a little sauermalz. Using that as a starting point you can very probably make a better beer by adjusting the calcium chloride and sauermalz levels. And you may even want to experiment with sulfate but for starting out CaCl2, Sauermalz and RO water are all you need.