After repeatedly bumping into drawer knobs at tight quarters, I put these together. No more bruises.

The dimensions were chosen based primarily on specific functional considerations (read: minimize bruises). However, the design is parametric (diameter, height, notch size, screw depth), if you find the notch too small (or your fingers too large?), the proportions too ugly, or whatever. Caveat: the Minkowski sum to get rounded edges takes about an hour to render (Core i5, 16G RAM), hence not releasing for Customizer. :)

Print without support and screw in. Screw hole may need minor cleaning/adjustment. It is approx. M3 tap diameter, just hand-drill as necessary (original knobs had ~4mm screws, but they were a bit too long and I just had M3s around, which worked fine with a washer).