Thanks Harmy and yoda-sama for the feedback.
Quality is important to us all here, so I've re-uploaded the Sources Documentary video to YouTube using the original .mkv. I think YouTube's re-encoding still resulted in the same loss of quality, but the bitrate appears to be slightly improved.
The video is now live on YouTube at the following link:
I also took the opportunity to improve information provided to those viewing the video on YouTube, such as annotations and a clear description explaining that Harmy made Star Wars DE, not me (an unfortunate confusion as a result of me uploading your documentary). Gotta make sure credit is redirected to where credit is due!
Harmy, as someone who I imagine judges the quality of individual pixels in his sleep, you probably will still be understandably dissatisfied with the quality of the video on YouTube. Still, judging from the views a comments on the first uploaded version of this video, I think there's an audience out there who will first learn about this project by viewing it on a widely-used site like YouTube, so this is at least a good way to introduce interested fans.
When I find the time, I plan to add English subtitles using YouTube's closed captioning. If anyone's interested in translating the dialog into another language, let me know (send me a PM)! Adding subtitles for multiple languages would allow this video to be enjoyed by a larger audience.