Really? I have that alone from trying to beat the first palace. Joker kept being one shot killed trying to reach the 3rd floor of the tower. When I finally reached it, I was pissed. Going back down to find a hidden key and getting one shot killed all over again for another 3 hours. After awhile I ended up googling recommendations. Ign recommends (so do many other places) to get everyone to level 10 first. I did this and still was one shot killed by the floor captains. The level differences between floors, non-captains and captains is huge.
If the rumors are true and the game is getting a switch version fallowing a different character's point of view, I hope they re-balance the shadows. The jumps in enemies power/level within the same palace are ridiculous.