For me, it all hinges on what constitutes “primarily commercial”. Even devlogs are a vague concept. Some are tutorials targeted at other developers. Example: "Can a tutorial video (which shows or teaches the creative process, or aspects of work, or even strategies to cope with work-life-balance) by…

Idea 4, may not be any better than the 1st 3: chop up the music into pieces and play the pieces in order, hopefully seamlessly. 

Idea 5: embed the music in code, not as a separate asset.