^Despite Holmes's reputation, the appeal of the original stories was never really about cunning mysteries and brilliant deductions, but more about the characters of Holmes and Watson and the colorful adventures they got into. In that respect, I think the show is doing rather well.
And let's face it, the reason this seems so much like all those other detective shows is because all those other detective shows are following the lead of Sherlock Holmes. It doesn't really follow to expect the seminal, defining work of the mystery genre to be radically different from the rest of the genre that grew out of it. Works that inspire whole genres often seem derivative to those looking back on them generations later.