I was very disappointed to learn here that the best I can hope for is a cheesy multi-layer acrylic case for what would arguably be a better RPi than the 5 Pi4s I have that are tucked into nice stylish FLIRC aluminium cases (one of them a snazzy Kodi box) and a Pi3 in its Flirc case running Octopi.
The advantages of a base over a hat in this instance in terms of airflow are clear, so I’m sure there would be good takeup for a more professional-looking case if it were available. It might even provide more of an incentive for users to buy the base in preference to the hat!