A leverless controller is supposed to eliminate sluggish joystick movements. Sometimes, it has only buttons or a mixture of buttons and keys.
The G series of Haute42 controllers can come in 16, 13, or 12 button editions in order to cater to your needs.
Donte Wilson is your guy if you are looking for stickless wooden controllers that have stylish button LED.
The RaidenBox is a mini all-button controller that is made of acrylic & nylon and is inspired by the Flatbox & Snack Box Micro.
The Steelbox is a mini stickless controller that has 14 buttons and switches, with the jump button being bigger than the rest.
The Paragon is a wooden stickless controller that has its own layout (unless you choose the standard layout).
The Caster Acrylic & Resin Fightstick DIY Enclosure by Raw Super Arcade comes in Vewlix, Noir, all button, and other layouts.
The DRMFTG DRM FL packs a lot of innovation, including many layouts, if you are willing to primarily use it on a desk.
Perhaps the most interesting aspect about the Sunga G1 stickless controller is that it has five more buttons than what we are used to.