I like the Steam Dock. Its specs are one gigabit Ethernet RJ-45 network port, an HDMI 2.0 port, a DisplayPort 1.4, and a USB C power delivery port. It also has three full USB 3.1 ports for peripherals.
It has an integrated 7" cable with a USB C cable on a 90-degree connector, to extend around back and then neatly plug into the SteamDeck's power port. Not so short that it stresses the cable, but also not with lots of extraneous cable length. It extends out at exactly the spot where you want to run it straight up and around the back of the Dock, right where the USB C power port is on the SteamDeck. Just long enough to connect and no more.
The dock comes with a USB C power cord, with a very small brick with a two-pronged wall plug.
The dock itself is tiny and very portable, 4.5" long x 2" wide x 1" tall. It is shaped like a stand that has a set of ports crammed into the back somehow. Very slick. It's made of nice material, and it has a little rubber strip in the cradle for the device to rest in, so you don't scratch the Deck. There is also a thin rubber layer on the underside, to avoid having the dock slide if placed on a smooth surface.
Are there other no-name brands out there for half the price? Sure. Most require you to go out and buy your own power delivery cable and wall adapter, often separately, though. You end up with extra costs and lots of annoying excess cables. Most have one or two USB 3 ports, but I've seen none that have three.
Those options are also usually built awkwardly, since they are made for laptops. They tend to be shaped like a dongle with the USB cable at the end. They generally don't have an integrated stand like this one. The Dock is pricier but a cleaner execution in most respects.