It is most definitely very crowded. There is no question about it. And I've always wondered how much energy these guys could possibly have to keep going that far into the future. I would assume that Han's age at the time of ROTJ is supposed to be about 35 Earth years. Plus another 25 for the NJO. We're talking that he's pulling Jack Nicholson's age and screaming his way through an asteroid field with his good old reflexes not hampered at all by age.