The mediatization of so many German families fools us. More or less mediatization meant that former Sovereign families kept their status. This means that even a Count Stolberg-Wernigerode, a Count Castell-Rüdenhausen or a Count Van Limburg-Stirum are "higher" than a the Prince Ruffo di Calabria, the Duke of Alba or the Duke of Norfolk.
That would be a very narrow perspective. I wrote that the marriage of Prince Albert with Donna Paola dei principi Ruffo di Calabria was not Ebenbürtig (in the sense of the Almanach de Gotha) but it was no mésalliance either. Since the family already was of high nobility in the 13th C, it belongs to the so called Uradel (ancient feudal nobility). It was in any way a better match than the one between King Baudouin and Doña Fabiola de Mora y Aragón, in terms of rank and anciennity.