What's your method to iterate over your business model?

Hey PH! We're offering a freemium service in B2B (https://axolo.co, we help tech teams working on Github and Slack reduce code review time). Most of our features are included in our free plan and we started last week our premium plan for companies looking for more customization. Right now, my main question for our upcoming features is to decide whether each feature should be in the free or the premium plan. Do you have any advice?