Controllers that have LED support usually have lights that can shine around their buttons or through their sides as well.
The Mojhon Fight Master—which has buttons that vary in their levels of concavity, convexity, and flatness—has an optional wireless connection.
To Live Is to Play is a store that sells this slim arcade stick compatible with Sanwa JLF PCB switches, including an adjustable shaft height.
The Furaipan by Akekon Dojo is essentially a frying pan with Sanwa buttons. Other options include a Sanwa lever edition.
The Alpenmeister TE's Hall effect switches allow you to adjust the button sensitivity, and there are also D-pad buttons near the aux buttons.
After the C16's immense success, Haute42 pleasantly surprised the FGC with the C16 Orange, which also upgrades the performance.
The Haute42 C-AS is a slim fightstick that lets you pick the joystick gate and button travel. It has optional analog sticks too.
The HyperX Clutch Tachi is the first arcade controller for fighting games with TMR switches, and it's also Xbox licensed.
The Haute42 E16 is awesome for having a mirrored layout for left handed players, but if you're right handed, the E14A is a solid pick.