00-01 Portland would be interesting with lots of passing and can you imagine a young Sabonis and Kemp on the same team with Sheed and Dale Davis for toughness and Pippen, Detlef, and Bonzi at the 3. Just a nightmare with athleticism for most teams to handle.
PG - Stoudamire, Strickland, Anthony
SG - S. Smith, Augmon
SF - Pippen, Schrempf, Wells
PF - Kemp, R. Wallace, Harvey
C - Sabonis, D. Davis, Perdue
The 06-07 Heat though I think could compete with the best of them given not many could handle Shaq let alone Shaq and Mourning.
PG - Payton, J. Williams
SG - Wade, E. Jones
SF - Posey, Kapono, Wright
PF - Walker, Haslem
C - Shaq, Mourning
SF is weaker, but in modern ball Eddie Jones would be playing SF and I think he'd do alright there.
The next year Heat is interesting because of all the midseason trades they had, but collectively at some point that season they had Shaq, Mourning, Wade, Marion, Penny Hardaway, Ricky Davis, Williams, Haslem, Blount.
The 11 Heat is also interesting. Obviously they had Lebron, Wade, and Bosh, and the main core at that time in Haslem, Chalmers, Mike Miller, Eddie House, James Jones, but the real key would be getting prime Mike Bibby, Jerry Stackhouse, Juwan Howard, Jamaal Magloire, Big Z, and Erick Dampier. They would have had the size those Heat teams always lacked and a true playmaker at PG in Bibby and an absolutely deadly scorer off the bench in Stackhouse.
Going back further, how good would the Lakers have been with Wilt, West, and Elgin all in their prime. I mean we saw them win 69 games and the title with old Wilt and West (and with Baylor walking away during the season), but that trio would have been basically unstoppable in their prime if they figured out how to make it work.