Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:5461133.

This stand holds the Steam Deck at a 10 degree angle and has a replaceable USB-C dock mounting bracket. The base is a few millimeters less wide than the space between the grips, so it also keeps the system centered on the stand. The dock is a CableCreation 7-in-1 USB-C Hub Multiport Adapter. The mounting bracket is attached with 5mm-long M2.5 screws and can be removed and replaced with something else, like a different mounting bracket or a piece of wood with a dock zip tied to it.

I have a blog post with more details. You can can also access the parametric design in OnShape.

UPDATE: This Cable Creation dock has insanely bright TX/RX LEDs on the network port. I modified the bracket design to cover them up and added a plug cover to block light from shining out to the front when the Steam Deck isn't there.