Hope you're being sarcastic, as that's the opposite of what Wellen wanted, I think. He wanted vassal relations to increase as your power grew relative to theirs to the point of being a bonus instead of a malus. That makes sense because the vassal-liege relationship goes two ways, in that the vassal offers his fleets to assist his liege in wars and in exchange the liege is supposed to defend his vassal if they're attacked, so a strong liege shows that he's capable of fulfilling his responsibilities to his vassals and thus they should feel secure.