Nice job! I did an experiment a while back and never shared it since the source uses Inventor 2017.
It’s not apparent, but many walls in LEGO bricks and plates have gradual slopes. This is due to how the injection molding process works, but also helps to provide a certain locking force. If the walls are perfectly perpendicular, the insertion force is sudden, but if the walls are tapered by just a bit, the insertion force is much more gradual (part removal is also considerably easier/smoother).
If you can, I’d suggest going to a LEGO store or shop online and buying the most generic parts to test against (assuming you don’t already have parts).
And for reference, the prints (sorry, don’t have any real-life pictures on hand):
Happy printing!