So, I would rate Miami's Big Three as the best core in the league. Probably the Thunder and Lakers in second and third place respectively and then the Celtics and Grizzlies in fourth and fifth.
A top five core sounds about right to me.
I think you're underestimating some teams because of how strong their top two is.
The Clippers have a better core than the Celtics because they have two superstars, even if their third guy isn't quite as good as any of the three core guys on the Cs. In fact, right now Paul / Griffin / Crawford is a lot better than what the Celtics have. Plus, their bench is far more productive and reliable, and they have legitimate size in the frontcourt.
I think the Clippers will have an elite core when/if DeAndre Jordan becomes a top 15 center, and/or, when/if Blake Griffin becomes a strong defensive player.
Until either one of those happens, I am leaving them on the second tier.
Edit: Or, of course, if they added a third star.
I just don't think it's really as simple as putting teams into "tiers" based on their best 2-3 players. Yes, generally that's a good guide, but I find it hard to accept the view that the Celtics are in a better position to beat the best teams in a 7 game series than the Clippers are just because they have 3 All-Star caliber players instead of just two.
The Clippers have two stars -- Paul and Griffin -- who are at a really high level. On top of that they have a great sixth man in Crawford and a deep and productive supporting cast. They're explosive offensively and they are one of the top teams in the league in terms of defensive plays made (blocks, steals, charges taken, etc). So far this season, at least, they are clearly one of the very best 3-4 teams.
I also think you're underestimating the Spurs. Duncan has had a great season so far. Much better than any of the players on the Celtics -- even Rondo. Parker is still one of the best guards in the league, and is still capable of taking over games. He's not as old as you think. Manu has declined quite a bit, but he still makes a bigger impact on the game than the box score suggests.
I think you, and most fans, are underestimating our talent. It's easy to go the negative route and write this team off based on a poor start to the season, but the fact that there is still very elite talent at the top of our lineup is undeniable.
Rondo is statistically the best point guard in the league right now. If you want to make a case for Paul or the injured Derrick Rose, fine, but he's clearly top three.
Paul Pierce is still the fourth best small forward in the league. He was even before that sick game against a terrible Cleveland team. Deng? Gay? Kirilenko? Galinari? Batum? Parsons? Don't insult me.
KG: He's the hardest to rank. I don't even know whether to rank him as a center or a power forward right now. But, I do know that Celtics fans seem to rate him as our best player. And, if he's better than Rondo and Pierce, then he's still a superstar player.
I'm not trying to undermine the talent on any of those other teams, but let's be realistic here. This Celtics team has elite level talent. I can't wait until they play up to that talent level with more consistency.
I'm not putting down the Celtics' talent.
They have three All-Star caliber players -- the three you mentioned. They also have the talent to have a very good supporting cast. So far that hasn't translated into a high level product on the floor, however.
I think Rondo has had a great year, but I don't really agree that he's statistically the best in the league. I still think Chris Paul is having a better year statistically. Russell Westbrook has had a great year, too. But Rondo is definitely one of the very best at his position.
My point in responding to Who is just that I think he is underrating some opposing teams, and that I think it's way too simplistic to say that the Celtics' core three are better than X number of teams and therefore they should be considered more formidable than all of those other teams.
Fact is, right now the majority of teams in the league shouldn't be afraid of the Celtics. By the end of the season that will hopefully have changed, but the Celtics just haven't put together enough good basketball to lay a claim to being among the best, at all.