It would be awesome, if we would be able to set multiple different key combinations for one action.
One example, that allows to add multiple combinations for one action is Fernbus:
Or more simpler version that limits you to maximum 2 keys per action is American and Euro Truck Simulator series:
Why do I feel this is needed?
I for example have 2 kinds of playing situations. Sometimes I can play with steering wheel. Sometimes not. With steering wheel some of the buttons I would like to map on steering wheel (like indicators) and without steering wheel I obviously would want to use keyboard buttons.