Shouldn't the Prince and Heir be paired together?

Pairing up classes is confusing and weird in general, but one question I've always wondered why the Heir and Prince class aren't paired together. I mean a Prince is an Heir just more specific, especially since both are gender locked. Also it'd make sense for Prince to be the active counterpart to the Heir. As far as where bard would go I'm not sure. I guess bard could go with Page (but both are passive) and you could put Maid with Knight. I don't know it just makes more sense to me for Prince and Heir to be a passive/active duo.