I am working with this package in a sandbox and struggling with the reporting side: https://www.beaufort12.com/mailchimp
Ideally we'd need to report on Contact > Mailchimp Membership *and* Opportunities (i.e. opportunities on a granular level, opposed to rollup opportunity values on the contact object). Suggestions very welcome! Am aware of third-party multistep reporting offerings but would prefer a more cost effective solution.