I still like the WCI arc however after the Pound reveal I like the arc a bit less now, for me I really enjoyed the first half of the arc but the second half is when things started to go downhill.
It dragged on for way too long, the arc could have ended much earlier but Oda decided to keep dragging it out.
Big Mom screaming wedding cake, I like Big Mom but her food rampage and seeing her scream wedding cake all the time was just really annoying.
Chapters in which it ended with the SHs about to be killed only for them to be fine in the next chapter, this is something that happened multiple times in the second half of the arc. You basically have a chapter in which it ends in a cliffhanger of the SHs about to be killed, but then in the next chapter they end up being fine. One time is ok but doing it multiple times isn't, here are two examples: Big Mom attacking the SHs with a tsunami as a cliffhanger and Big Mom's ship seemingly destroying the Sunny as a cliffhanger.
When it comes to Luffy vs Katakuri, I personally enjoyed the fight however the fight did dragged on for a bit too long. The only two things I really didn't like from that fight was Flampe, and Oda not showing the last attacks of both Luffy and Katakuri hitting each other.
I personally enjoyed Sanji's character during the arc, however I didn't like that Oda left his family issues unresolved.
Smoothie and Compote, two female characters that Oda hyped up but then didn't show anything from them. Smoothie has the same rank as Katakuri and Cracker and was hyped up to be one of Big Mom's strongest fighters, and yet throughout the arc she didn't do that much. Katakuri, Perospero, and Oven were doing all the work, when you have two non Sweet Generals doing more work than a Sweet General that's a problem.
The Seducing Woods, I actually enjoyed the Seducing Woods in the beginning of the arc but the return to the Seducing Woods in the second half of the arc was horrible.
Nami getting Zeus, I didn't like it then and I still don't like it now.
I think that's pretty much it, those are just my personal issues with the arc.