While that would work well, it isn't at all how Patreon is meant to work, though. The way Patreon works is you are donating money..not paying for a subscription or membership. Naturally, the more you donate, the more the devs offer, in many cases..but, those donations are just that...donations. You're donating for their cause. Their cause is to work on their project. In essence, your donations are to help them continue their projects. You aren't buying anything.
I agree...if I'm throwing money in someone's account, I like to see steady progress, but that isn't required. This is also why I quit donating on Patreon ages ago. I've been stung by way too many abandoned games and ghosting devs.
But, point being...donations aren't for purchasing subscriptions or memberships. The word donate means to give a gift with no expectations.