Hi @email@example.com! You can tag subscribers who opened your last email as "engaged" and create a segment for them that will separate them from those who might not be as engaged. Currently this tagging of opens is a manual process. You can also add your requests to our Feature Request topic!
For even more options, you can create conditional content based on tags as well: https://help.convertkit.com/en/articles/2502501-conditional-email-content-based-on-tags51