I remember testing out the Tempostorm version of "Midrange Shaman." It was gutless and felt like it had no win condition against the massive removal kit of a Tempo Mage. The Bloodlust deck is slightly better, but if I was going to play an OTK combo deck I would just play Druid.
Yeah, the major issue with Shaman has been that every other class does the strategy better. Only recently has Face Shaman been able to give Face Hunter a run for it's money.
Mid-Range/Secret Paladin > Mid-Range Shaman
Freeze Mage > Malygos Shaman
Zoo > Bloodlust Shaman
Mech Mage > Mech Shaman
That said I was able to push rank 3 the month I was focused on Shaman only play. Mech shaman was really strong at the time because it wasn't super popular like Face Shaman is now.