[CamperBob2]

Creators get paid, don't feel pressured to provide refunds, and patrons get a little sign-on discount.

This seems like the key. Instead of making any decisions about payment scheduling options, design your system to allow for all of them within reason, and give the creators a menu.

If you don't offer your users enough options, you will eventually be out-competed by a patronage service that does. Hardwiring your system to a model that happens to work for you simply ensures that this will happen sooner rather than later.