"New game plus - quests will have no rewards..."

[linay]

My only dissatisfaction is that you have to do it in major chunks. Last I checked you have to choose a specific expansion, not specific quests or even patches.

You do it by chapter, not expansion. The example given shows Heavensward alone is divided into 4 chapters or so, and that's just for MSQ. Later on, they will add job quests and side quests, along with ARR MSQ, so not sure how those will be handled.