The "Bitcoin Engineering Task Force" (aka Satoshi) already decided that SHA-256d is the best hash algorithm for Bitcoin. 
Satoshi (aka DARPA) designed bitcoin by the end of 2008 to substitute gold because by that time US financial system was teetering on the brink of total collapse with no gold in store. This is not necessarily a bad thing. But it's time for the lizard to sacrifice the tail and break free!