Epsom salt will dull the brightness. Epsom is great with dark beers, but not a light beer. Go get a light beer and drop some in and try it. I don't think it's appropriate for the style.
The CaCl is great for light beers, however not a bock. Your trying to get a dryness that only Gypsum can obtain. When you use CaCl you get a very soft "wet" feel, which is opposite of Gypsum.
I've done Gypsum and CaCl multiple times and concluded that Gypsum alone will give you the dryness. Regarding concentrations? I use 3 grams of Gypsum per 5-6 gallons and it's perfect (don't have the software to calculate it, not sure I care). Stay away from the others. After your done fermenting and have a glass of beer in front of you, that is the time to experiment with adding Epsom and CaCl to see if your idea works or not.
Trust me on this, I've done many versions using different concentrations and Gypsum alone won.