If this game had the potential to attract a speedrunning community, the restrictive timing would have serious potential to be extraordinarily interesting.
But yeah, it can be a bit awkward. Makes for interesting planning sometimes.
It wouldn't be all that difficult to have all the main quests finished by the end of Day 2 with a little bit of planning. I had them all done on Day 3 in my New Game+ Hard run. The time consuming sidequests all involve either going into the Warren or coming back to NPCs on consecutive days.