What team has more to offer than Boston in 2012? ... Nobody
The Celtics are the best positioned team to steal Dwight Howard away in free agency.
It's way too early to say, because we have no idea what the CBA has in store, and what moves will be made.
But I would argue a team like OKC with Durant and Westbrook would have a ton to offer. Or, if he wants to play in the big city, NY will put him next to Amare, which would be an interesting match. Indiana has Granger and Collison among others. Golden State has Curry, Ellis, and Lee.
Also, a team like Washington with John Wall has a good shot as well.
Basically, I think you are greatly overrated Rondo, if you think he alone will attract Howard to Boston.