Johan Flikweert suggested calling a nanoflow from a microflow, but he limited his use case to reusability for validations: https://community.mendix.com/link/space/microflows/ideas/4206.
My idea goes a bit further and was inspired by Jason Teunissen.
Sometimes, you want more than just showing a page, validations or a dialogue message. You could work around it by starting your microflow call from a nanoflow, executing the microflow call and then finishing the clientside actions in the nanoflow. I want to reverse that instead; just as you could trigger an open page and validation flow and show dialogue from your microflow, you could call a nanoflow, which gets executed once the microflow is finished and performs more complex client-sided logic.
This would enable client side interactions such as showing a toast message instead of a dialog, redirecting the user to a page, opening a new tab in your browser with a new page etc.