Brett Partridge is 100% Red John
Think about it:

-He was in the very first episode, and the first lines he ever said was "Red John was here"
-Every time Red John kills, he says it wasn't Red John, and every time a copycat kills, he says it was Red John, therefore trying to trick Patrick
-His description fits Red John
-Voice also matches perfectly
-In Season 2 finale, when Patrick meets Partridge, they talk, Patrick goes away, then returns quickly to 'shock' Partridge. Later when Red John meets Patrick, he goes away, and quickly returns to 'Shock' Patrick, ie. Returning the Favor
- Red John is described as Patrick as a 'Showman', and in first episode of series, Partridge reenacts murder like a 'showman'
- Name sounds close to 'A Brace of Partridges" which is connected to William Blake.

How can you even make a better case for anyone else????!!!