As long as it is not possible to automate it, as many as you can. No worries :) We're still well within what's economically viable for me, even on the days with the all-time-highs and beyond. In other words there is plenty of room to grow, and you don't need to worry about it. Please keep going hard as you have been, I love to see it.
My main goal with this application is not to make a ton of money, but to provide a way to add massive amounts of data to the chain, thus increasing the value of the network as a whole (including token values hopefully)
This only becomes an issue if full-auto mode becomes possible. And in that case, I'd probably look at imposing a limit of maybe a thousand videos per account per day or something.