Holmes is a master of logical and deductive reasoning able to see in a second what others can't find after hours of strenuous searching. He seems to be an expert at everything and can tell you where you're from, what you ate and your best and worst habits after simply looking you over.
He's England's most famous detective and solved some the most difficult cases in Scotland Yard history, but he is also a flawed human being. Doyle did this on purpose to show that a genius can't be absolutely perfect and there has to be a trade for such amazing skills. He was a known opium addict and socially awkward.
Once you placed him outside the realm of a case, he was lost. Dr. Watson was his anchor to the real world and suffered through more than a few condescending insults. There was a tendency in films to portray Holmes not as this flawed individual, but as the perfect detective. Even when Brett would take to the opium pipe, he did it in a refined way.
Doyle didn't see him that way and Holmes was known to be hot headed and not afraid to fight. While the Robert Downey Jr. Holmes is the wildest so far, it's the one most true to Doyle's vision.