 Have you ever considered having someone help editing your videos? I mean, if you're happy with the progress you're making right now, an extra pair of hands might get in the way of your creative process.  However, if there's other projects you'd like to finish as well, but can't because you're too busy with this gigantic History of the Universe video, don't you think it's worth the mild sacrifice of creative control?

I'm asking this not as some impatient fan but as someone who can't imagine crafting one youtube video for multiple years in a row.  I'd personally lose sight of what I was doing just a few months in and might grow to despise what I once promised to myself I'd happily accomplish.