Old Thresh Bio was better then the new one by far for me....
Not sure if anyone felt the same but simply this new one just went crazy and became evil where as the other one was just evil period plus the whole chain warden with keys and lamp fit so much better with the old bio since it something that is pronounced with that type of story rather then some guy guarding a vault.
It also just reminds me he had the Sargeras Effect as I call it (anyone who is a World of Warcraft lore junky knows what I mean) which was just being around evil things for too long until you just became evil yourself which is fine to do. This however was executed poorly IMO with how the character was originally created given he looks like something in a Jail house or Asylum, not guarding a vault.
That is my thoughts.