I felt like the setup of the first part was at time a little frustrating, since I started it during a time when Keras had switched to a newer version which wasn't compatible some of the utility code that was written. Add this to the newbie factor to notebooks, and it was a pretty rough first week or so to setup and get actual learning done. It took me a bit of time to realize notebooks were more like repeatable trains of thoughts than well-written production code.
The other thing is that some of the supplementary material was really long and at times made me feel like, why take this course instead of just going through a course mentioned in supplementary material (e.g. CS231n wrt CNN's)? I think I ended up spending hundreds of hours reading/watching/practicing CNN's by reading papers, watching Karpathy's 231n videos, and doing a couple tutorials from data scientists who elaborated on a specific problem they were solving. I guess at times when watching Part 1's videos and doing the notebooks, I didn't feel like I was 'getting it' as much or as fast as when I was getting the information from other means.
While the forum discussions can be helpful, it was also wadding through a ton of unstructured content. And the service they used for the forums hotmapped the find shortcut to their own built-in search, which was a little annoying. I don't know a great solution to having more structured data, but perhaps adding some of questions that were answered to the lesson's Wikipedia. Or maybe splitting the technical issues from the high level concepts.
Lastly, I think it was either HN or /r/MachineLearning but someone had suggested a book regarding Machine Learning and hands-on Tensorflow usage which I picked up, and I felt like my pace of learning really sped up afterwards. I think part of it was Tensorflow has a lot more written about it so when you encounter an odd problem, chances are someone else has something to say about it.
All criticisms aside, I think I'll try going through Part 1 a second time around prior to going through Part 2.