Regarding anything Open Collective — we tried using their platform for quite a while to raise funds for our projects, and it's almost unusable with all of the bugs and awkward user interactions (for both individuals/companies wanting to contribute to your project and the project maintainers themselves). Open Collective is still plagued by these issues over a year later. I would use a lot of caution if you're considering using it.

Patreon is what we switched over to and haven't had any headaches since leaving Open Collective. I'm excited to see GitHub Sponsors support teams/orgs, hopefully sooner than later 👍

Regarding individuals expecting higher priority support with their small financial contributions — this is something we've not really run into at Roots while raising funds for over a year. I think it's important to make it clear to your supporters what is included with their contributions. You could have tiers for companies that pay significantly more money with some support time included.