Though, I'm 98% sure Sting is still with TNA. If he were signed with WWE, he'd have appeared by now.
Just because Sting has not signed with the WWE yet does not mean that he's still with TNA.
Bully Ray may very well have more overall value than Sting or AJ Styles. He is a role player that WWE needs.
And why's that?
Bring Bully Ray into WWE,
As Bully Ray or as Bubba Ray, I thought you wanted him returning as the latter?
this instantly places Bully as a top guy, him being a natural bully places him as the exact thing all the faces in WWE are supposed to hate
Winning a match in brutal fashion does not place him as the "top guy." He's a heel, heels aren't "top guys," they're supposed to be hated upon. Sure there's the odd few that will still cheer him on but as the heel, you're not supposed to be the "top guy." The top guy is the biggest draw, heels aren't big draws and if they were, the TNA figures are lying to us. They would have been higher last year had the World Champion been a big draw.
All he needs to do is a "Do you all remember me? You know what, I don't care if you do, you're all just another in a line of people who are going to get their asses kicked."
It's the WWE. They're likely to keep him for what he's known by the majority as; Bubba Ray Dudley. Not many WWE fans watch TNA so how would they know where this gimmick has come from? Like Killjoy had stated, the WWE Universe will be asking about his tag team partner's whereabouts. Now assuming they do allow him to use the Bully Ray character, there's only so much he can go as far as trash talking is concerned. They're TV-PG, bear that in mind.
Set him loose on the WWE upper midcard. Profit.
Because he did wonders for TNA didn't he?
His idea is probably to keep pushing for Punk to come to TNA. Which is even less likely.
Bully did in fact tweet that he wants CM Punk in TNA. So you're probably right, he may think TNA is the right place for CM Punk. That's all that the message could have meant. Why else would he add @ImpactWrestling to that tweet? That doesn't make any sense unless he wants to put his job in jeopardy, but I can't imagine why. From what I've read he's happy where he's at, especially if he wants Punk with him in TNA. It could also mean a face turn. I don't know why he would remain a heel in TNA so he may have meant giving back to the fans what they want to see. On a side note, you don't know CM Punk. When he threatened to leave WWE (Kayfabe) in 2011, he said he would go to ROH or NJPW. He's angered with the WWE right now, I would imagine a lot after they toyed with the Chicago crowd so a jump to TNA isn't a complete no-no to get his message across.