One of the bravest things about ESB was splitting up the popular double act of R2 and C3PO for most of the film and having Mark act with essentially a puppet and a prop.
The end of the film showed the potential of splitting another popular double act Chewie and Han.
Part of me wishes Chewie stayed on the Falcon with Lando for the big battle in ROTJ as he hardly has anything to do on Endor (other than the Tarzan gag).