I didn't really get that feel. I suppose the B-Wings and Admiral Ackbar and possibly the Ewoks were the only toys that actually 'came' from ROTJ, though the main characters changed enough that they released, for example, and Episode 4 AND an Episode 6 version of Darth Vader, but the success of the Original series was as much a surprise, I think, to Lucas as it was to the actors. Admittedly, Alec Guiness and Vincent Price wouldn't have got involved if they hadn't seem something, but no-one was expecting what happened.
The recent three Episodes were the other way around, it was like... 'Right, first up, what kind of marketable material can we fit into this film? Once we've sorted that out, we'll start looking at the plot etc.'