I actually loved Okumaru's and Futaba's Palace puzzles...the Zero-G Tubes puzzles were challenging, but not tedious and the Binary Puzzles in the one chamber were well done in Futaba's...I still had to get a note pad to write that codes down, but still manageable!
The Vault Codes in Kaneshiro's were a bit...cumbersome, but it's my own fault I had difficulty with them, as I didn't know I could shift to different parts of the Inventory Screen to check Key Items like the Journel Scraps!
The only parts of Palaces I REALLY hated was the latter half of Kamoshida's Palace, with the Knight Enemies being weak to Ice, slowly draining Jokers SP and the Chapel Stealth segments, having to go back through it from the Safe-Room anytime you entered the Palace at the point.
Also, fuck EVERYTHING about the Mouse Segments in Shido's Palace! I never actually got caught by an enemy in Mouse Form, but those segments are way too stressful and tedious...oh, and did I not mention how in the Third of the FOUR Mouse segments, there are Titania's who can put your whole team to sleep with Lullaby and Spam Mafreidyne, quite easily capable of killing Joker?!
tldr; Shido's Palace is just the FUNNEST PLACE IN THE GAME!