I appreciate the OP's sentiment... Having these should be "prestigious"... but the "prestige" mechanic as implemented in the game isn't the right approach.Maybe way cooler profile pics, or some kind of nominal benefit (e.g. questing with goldpool he gives you the Pittance (5*) and Prosperity (6*) effects to get a smidgen of extra gold). This wouldn't be game changing (after all, who actually uses these masteries? Clearly they aren't overpowered)... but it would do something for having and using said champs.
And the award for Most Ridiculous Suggestion of the Year goes to *envelope please*…