The Jeremy Brett adaptation is so good, huh. It is hard to picture Holmes and Watson and their Victorian world any differently after watching the Brett series. I think 'The Speckled Band' or 'The Six Napoleons' might be my favourite Brett episodes. . . I do agree with you about the Red-Headed League though, also the 'The Man with the Twisted Lip' (Holmes liked his opium). I think in terms of the stories themselves, from memory I think 'A Case of Identity' or 'The Five Orange Pips' might be my favourite.