First off, Big Meme is capable of imbuing her attacks with adCoC.
Secondly, Big Meme isn't as slow as your making her out to be. She was able to keep up with base Kaido, and catch Marco.
And thirdly, Zoro does not have superior CoC, especially considering he had just learnt to imbue his attacks with CoC, while Big Meme has been doing it for years.
Whether Zoro has superior attack power is debatable as while Big Meme's attacks portrayal-wise have been rather lackluster compared to her contemporary Kaido, she can imbue her attacks with adCoC, meaning she probably has superior AP currently.
Reply back once you've finished inhaling your