Good to hear! From a user-space, I've been enjoying video game emulation for over 15 years, and as such, I've built quite a collection of input devices. Within the past two weeks I just added a Raphnet N64/Gamecube to USB-HID adapter (v2.9), as well as a 4-port Mayflash Gamecube to WiiU/USB-HID adapter.
The device I am looking forward to testing the most however is the Mayflash Dolphinbar. It not only acts as an incandescent LED source for Wiimotes/Wiimote Pluses, but also has it's own built-in Bluetooth that intercepts and pairs with the Wiimotes and converts the input data to a standard outgoing USB-HID interface. This of course means that the Wiimote can be used as a Mouse, Media Remote, Gamepad, Racing Wheel and best of all, Light Gun for any USB-enabled device that excepts the standard USB-HID interface without any configuration outside basic button mapping. Good Stuff!
Anyway, as I understand it, the Kodi input layer that was designed for Retroplayer was recently merged and can be found in the Kodi nightlies. I realize that currently this only grants the ability to navigate Kodi with all forms of new user periphials. However, I would be happy to begin testing devices for OSMC whenever you guys believe it is ready to do so. I've never contributed feedback to an open source project in any official way, so please excuse my ignorance on this issue or if I have jumped the gun on my offer to help.
As always, Thanks.