The question on forum someone asked about concertinas in E flat ( etc..) Got me thinking how odd it is to try exotic keys on concertinas.
C sharp is example as there's a need for several of your sharp notes in sequence to be used.
I have button accordion ( my father's) keyed with a row in C sharp and row in C major.. where that sharp row sounds so lovely to play, and with comparative ease..yet switch to anglo ( 30 key) and fingers Jump all over the place to reach the notes; its Ike going for a ride on a rocket to a very distant planet, of which there is a sense of familiarity, and yet, at the same time, being aware of a slightly mysterious exotic world.🌝
A wholly philosophical thought 🌝