I am in a similar position with regards to the Charlies.
I bought a set of CH and they are fine and work perfectly well, just something within my OCD that want’s the Charlies to match the Alpha and Bravo in terms of look, feel and quality.
As for accessories.
I have the touch brackets mounted from Stay Level Avionix which mount to the top of the Alpha and Bravo so I can mount 2 15.6’ touch pannels that I use for Air Manager gauges, maps, etc… also has a spot for a Knobster which I’ve sttached.
The bracket is nice, and I did look at it also but another forum member @Crunchmeister71 came up with a velcro solution shown here