If you are looking to mainly get into disc brakes on a road bike I assume the Motobecane is only a rimmer??? My only thing is, until you ride the Bianchi to make sure it will be as comfortable I would not unload the Moto prior. There is a lot to be said (well, all is to be said) with comfort over looks for sure.
If you unload the Moto and get the Bianchi and it does not jive with your body you are going to be miserable and disgusted with yourself. Good luck and enjoy.