Trying to avoid reading anything about the game, so apologies if this has been asked in some form before, but here goes: is there a system in place that would make it hard or even impossible to finish dungeons as soon as they open (as in, in one night) on normal/harder difficulties? In P3 you got tired if you spent too much time in the dungeon, and I'm pretty sure there was something in P4 too that made spending a forever in dungeons impossible... Like maybe restoring SP in the dungeon was super expensive, so at a certain point you'd have to go home and sleep? Can't remember.
In TL;DR form, can I realistically tackle dungeons, spend time grinding and finish them as soon as they appear, in one in-game night?
I'm asking cause I can't decide on my starting difficulty lol. On one hand, playing on safety would likely mean that I can finish dungeons on one go, leaving me with more in-game time to spend doing social links and other optional stuff. I've never thought the battles in P3 or 4 were particularly engaging, either. On the other hand, I've heard the battle system is slicker and more fun than ever before. Might even enjoy the difficulty this time around.