The opening of ROTJ sums up everything that's wrong about the film, it's a pointless rehash of the opening of ANH (pointless because without the battle the scale of the ship no longer demonstrates the strength of the Empire) and they cut away before the sweep is finished.
The object that should represent the might of the Empire (the Death Star) looks so tiny and fragile.
A better opening would be to trump the Executor reveal in ESB.
Show the Executor arriving to drop off Vader with support ships and then have it suddenly dwarfed by the huge scale of a gigantic Death Star (with lots of building activity) popping into view as the camera pans down.
That way you get a sense of progression.
ANH shows how big a Star Destroyer is.
ESB shows how big the Executor is in scale with the Star Destroyer.
ROTJ shows how big the Death Star is in scale with the Executor.
Something like (only better and possibly from the other side which would mean a new model would have to be built or matte painted) :
