Honestly surprised most are liking Chapter 6 best so far, even with it having my favorite episode of the series, the Roots of All Evil two-parter. Well-liked and generally regarded to be a good chapter as it is, the people who haven't liked it have been far harsher on it than Chapter 4. If you're curious as to how I would rank the chapters, it would be like this from worst to best...
6. Chapter 1
5. Chapter 3
4. Chapter 2
3. Chapter 5
2. Chapter 6
1. Chapter 4
Chapter 1, despite being far better than what it's made out to be, is easily the show's weakest part as a result of Atomic Cartoons still learning the ropes. Chapter 3 is a great holiday special, but I'm not ranking one special higher than a batch of episodes. Chapter 2 is even more underrated than Chapters 1 and 3, some people were even calling it confusing when I was able to understand everything going on in it perfectly and it only gets better the more you see how they're setting everything up. Chapter 5 is pretty good, even as I actually like Father of the Bridlewood and the Halloween special better than Family Trees. Chapter 6 was an awesome end to the show's first story arc to me and I already really like the setup for the next story arc in my favorite special. Chapter 4 is still my favorite part though with it having my second favorite special, my second favorite episode, and my all-time favorite part of the story, Misty's reformation.