The most effective way to win a title, with the exception of landing a top pick, is by complementing a conference semifinals or even conference finals worthy team with a big man star on a falling team. 

It worked with Detroit (Rasheed Wallace), it worked with Miami (Shaq), it worked with Boston (KG and Allen), and it worked with LA (Gasol). 

Who can be such a talent on a falling team for the Heat? Bosh and only Bosh. 

Just look at the options, none of the following teams have a sidekick for Wade that can deliver the Heat a championship other than Bosh:
Indiana, Charlotte, New Jersey, Milwaukee, New York, Washington , Phoenix (Stoudamire too injury prone), Golden State, Minnesota (because Jefferson isn't going anywhere), Memphis, OKC, Clippers (although Kaman would be a nice complement), and Sacramento. 

Even if you look at playoff worthy team there isn't a plethora of tradeable talent that will win us a championship available. 

The truth is, the Heat need Bosh. We can always replace Beasley, but the Heat need Bosh. Wade will not win a championship with any other possible current NBA player the Heat could trade for, with the exception of Amare if he's healthy, other than Bosh.