To be clear, speaking for myself I didn't see dropping NPO as a harsh term. It's understandable. If they could get us to drop NPO, they removed all reason for continuing to attack us and hence peace was sensible. Otherwise, they'd continue attacking so as to neutralise one of NPO's allies. Harsh terms are to my mind extorting massive reps or imposing viceroys or decommissioning projects or a whole variety of dick moves that nobody in this game has ever bothered to dream up, e.g. refusing to let the enemy alliance receive rebuilding loans from banks afterwards and having someone from the victor's alliance have access to the alliance bank to ensure compliance. PnW has never even SEEN harsh terms because nobody hates each other enough.
Whether we would ever accept such terms is of course a totally different matter from whether the terms were "harsh". It'll be a cold day in hell that any alliance of mine drops allies at the behest of an enemy alliance.