Nick, you raised a good question about the dynasties...
I normally apply the logic that if the "heart" of the team stays, the players around don't matter. So for example I think you could count the entire Magic Johnson championship era (80-88) as a dynasty. But this lakers group, if they were for the sake of argument win the next 3 years, would be a separate dynasty because Shaq was ultimately the anchor of the old dynasty, and Kobe would be the anchor of the new one.
Note - I only apply this to Basketball. Other sports can be very different.