If you're comfortable building NickelMenu from source, the latest master branch in the official repository has "bluetooth on/off" instructions implemented.
Code:
nickel_bluetooth - one of:
enable (4.34.20097+)
disable (4.34.20097+)
toggle (4.34.20097+)
check (4.34.20097+)
scan (4.34.20097+)
Or maybe @geek1011 can make a release of NickelMenu 0.5.5