"Probably the next area of work for keyboard shortcuts will be to do multi key sequences."
What you mean?
Maybe the possibility to crate shortcuts commands like in Autocad or Rhinoceros?
e.g.

OF --> space bar = offset
BEV --> space bar = Bevel
BOO --> space bar = boolean
BOU --> space bar = boolean union
BOD --> space bar = boolean difference

In Autocad you can use space-bar or enter key to execute the command

I hope you can add that type of shortcuts commands.