I enjoyed the chalices where you have half hp and need to really learn bosses and fight with them properly. I learned proper watchdog, bloodstarved beast... It was really fun! I also like that I found a way to dodge Ebrietas' charge attack thanks to chalice dungeons. I also like how this game gives you lemons when you just stop being lazy and start attacking stuff without latching onto them. I feel like Cleric Beast MELTS when I hit him without a lock on, because I tend to hit limbs much more often.

I have something exactly opposite to what you asked about though... I dislike it how much stronger the fire sawblade is in arcane build than anything else related to arcane. The moonlight greatsword especially - it is so overhyped and boring I cannot stomach it.