From the picture, you can see my hook is mounted on end grain lumber, so I needed to be sure the screws were solid. Eventually, a Turkish hanging lamp was hung on this hook (and another off camera). Aesthetically, since I was mounting these hooks quite high, I wasn't concerned with the visibility of the screws.
My model was printed with Atomic Filament Majestic Brown PETG with a 0.6mm nozzle and 0.3mm layer height and 30% infill.
The author remixed this model.
At the request of @Nikki, I'm posting this remix of her Hook-3 design. For my use case, I wanted to directly mount the bracket to the wall. I made the hook shorter (i.e. decreased how far the hook stuck out from the wall), and added more of a base to it to allow direct-mounting. The screw holes are countersunk for some deck screws I had laying around.