Many fightsticks—especially 3D printed fightsticks—are made out of all sorts of plastic, and the right kind of plastic can still be durable.
The Ekkusu Fight Controller is a leverless controller that is thicker than average, allowing it to use premium buttons like Sanwa.
If there's a most innovative award, the JTechWorkshop would definitely be a contender. Its leverless controllers have highly custom layouts.
The nanoGRAM is the size of a card, making it one of the smallest Smash controllers (if not the smallest).
The GRAM PRI$M allows you to play Smash and other titles ergonomically with a variety of possible layouts.
The SGF Faust is a mini stickless controller with LED plus a TRS jack for external input sources like foot pedals.
The Glyph is a modular all-button controller that is available in layouts for games from Smash to Street Fighter.
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.