That's a rather interesting chart, thank you for that, I bookmarked it. Self distributed CDs are also an option, but we would have to spend the money up front to get them made, and it would only be in small quantities. I don't like the idea of an album going out of print after 300 copies are sold. I know there's the digital only option, but my dream goal has always been to release a CD. And from what I've seen, metal fans are much more likely to buy physical formats than fans of a lot of other genres (metal fans also buy a lot of vinyl too, and some even cassettes).
EDIT: And another thing to consider in that today's musical landscape the real money is in playing live and sell merch, and it's a lot easier to do that with a label backing you with promotion.