Saturday: Combining Zaragosa and Real is not doable, in my estimation, unless your goal is to haul the mail all day and never stop, not even for a nanosecond. I've done Zaragosa and the falls and some offroad and it takes a full long day just for that ride. Adding in a southern route out of Zaragosa thru La Bolsa and Dr. Arroyo, then over to Real de Catorce, and back up highway stacks 645 KM, 12 hrs, into one day. Hardly a minute free to sightsee, and a nightmare if someone has a mechanical. Most people hitting up Real and Mextrek take a full week, I think. Riding pavement to Real and back is a full day, if you want to experience Real.
More experienced Mexico travelers wanna chime in?