How much is enough?

Hallo to all Freelancers

I’m starting an online academy. So it’s a start-up. I’m in the process of looking for funding to go into full production, but it’s though to find seed funding and I need input.
(I’ve designed all the content up to now in Hype and I want to stay in Hype.)
Access to educational content is monetized and managed with a Learning Management System.

The human resources weight on the budget is heavy, but what if I offer the people that develop the product/content, (which includes content specialists, developers and translators) a percentage of income generated? Which means that they don’t get paid right now for the work, but as the product sells, they start getting more and more income. And continues to get income for as long as the product is sold. The more product is designed, the bigger the eventual income. To get the academy to profitability, I must design content as fast as possible. (I will work on the same basis and will carry the same risk as any developer.)

So my question is: How much is enough? For a freelance developer to take this risk, how much of the sales that is generated (in percentage) will be enticing enough? Or would you even consider such an arrangement? Am I smoking my socks?
(At this juncture we have to assume that I have done my homework and there is a market for the content.)

As always your input is valued.

Unless you are reliably and consistently providing enough customers/income, you cannot charge too much. If you are just starting, you would probably want to take around 10-15% - this will cause an influx of material on your website and eventually sales will rise enough for you to have leverage to increase your commission to 30%+

Ok then. To all developers: No disrespect intended. Thanks for the reply PappaSmalls.