Maximize window after cmd+tab switching to app with only one window minimized?
Hide the app instead of minimizing it
Instead of minimizing the app, try to hide the app instead by using CMD+H. Functionally it appears to be the same for your use case, and when you switch back to the app either by clicking on it on the Dock or by selecting it in the App Switcher, all windows for that app will reappear in the positions they were when you hid the app.