@Riot what's your opinion on enabling Thresh to jungle?
I love Thresh, he is my most played champion. And you know what? He works well in the support role namely because he is a jack of all trades, master of none. His abilities are decently powerful to where they can serve any purpose in terms of utility, but not powerful enough that he outclasses other champions in the categories. He can go for picks, but isn't overbearing in this sense due to the ease of dodging his hook (but can make someone who's mastered Thresh quite annoying). He can peel, and he can also do small forms of engages. But if he goes for one action, he can't do the others at the same time. This style of a champion's utility would also work quite well in the jungle rather than just support.
However, there is one simple thing keeping Thresh was working in the jungle. And that is his lack of jungle clear power. To fix this, I propose one small change that will not affect Thresh's laning power in any way. Make his Flay (E) active deal bonus damage to monsters (about 50%). Thresh's basic attacks deal enough single target damage, but he doesn't have a strong form of AoE clear. Adding bonus damage to monsters for his Flay would be enough to increase his clear speed so he can keep up with other junglers. The best part of this: Thresh simply put would not outclass other junglers. His ganks wouldn't be consistent, since if he wants to keep his clear speed up, he'd have to max his E first rather than Q. He wouldn't be overbearing on objective control since he has no innate sustain or excessive damage. And his late game scaling isn't so high that he could just play safe then beat other junglers outright. The only real thing Thresh would be strong at is counter-ganks, but he would still be outclassed in this sense by higher damage champions such as Gragas or Elise.
In addition, if Thresh is allowed to jungle and he gets even a small amount of popularity in the jungle, it would force people in the same games to choose a support other than Thresh, potentially opening up supports to a more diverse selection.
I'd love to hear opinions from other members of the community as well as Riot on this. Personally, I see it as a "why not?". It doesn't add power to his laning power, and only allows him to work better in another role.