Feet are one of the most common ways to make arcade sticks more stable on a desk, and oftentimes, these feet are made of rubber.
Retro Stockpile offers enclosures in the leverless & fightstick formats that can also come preassembled with buttons and other parts.
The X8 is PXN's debut WASD-style controller that sports some interesting artwork which is refreshing to see.
The Zero Two is a modular controller that can be ordered in lever or leverless format—as well as preassembled or DIY form.
The Zero One is available in multiple layouts and colors—plus preassembled or DIY formats—and an overall modular design.
In addition to a Sanwa joystick, you can order the Joytron EX Revolution with a Crown lever variant of your choice.
The Taito Egret II Mini Control Panel can be used with the Egret II Mini arcade cabinet or as a PC arcade stick (with the proper drivers).
Although it has a bat-top joystick, the PC Ranger's octagonal restrictor gate makes circular motions easier for you.
The RAC-J800B, part of the J800 series, is an excellent all-button controller that is available in multiple variations.