That's kind of one of the issues, is that its a bit harder to track how much someone's upvoting is worth. It's something that's value is speculative, even with a pegged SBD. You can't really count on the rewards until they're paid out. Instead, Patrons and Backers should be treated similiarly but also differently, like 2 sides of a coin. Especially if something happens and theres no post rewards coming through, patrons would be able to pick up running costs.
That being said. I think a real good way to give back to supporters is with a lootcrate-esq system. The problem with that is a scenario where people are signing up for the loot and dont care about the content. And that's kind of bad. A remedy to this, is to mix the items that go in these crates so that they're steem based and also Steem marine related.
I just need to talk to someone who has experience with this. I want to get it right, and I want to get it right on the first try. xD