Hey Sean,
Good question. There is no best theme or framework as far as we know, though some themes (like Avada) have made a special effort to integrate The Events Calendar into their framework for smooth compatibility.
The sheer number of themes and frameworks out there makes it tough to test (or even guarantee) compatibility with everything. For that reason, we offer a full 30-day refund on all purchases so that you have a chance to test our plugins with the themes of your choice and find a combination that’s right for you. I find that test driving the plugins in your own environment is the surest way to getting what you need, so this should afford you the chance to do just that.
Does this help answer you question? Please let me know if you have any others and I’d be happy to answer as best I can. 🙂
Cheers!
Geoff