So here's why I would NOT bring over any of the following...
Kurt Angle: The man is a legend, and has been damn good in every company he's ever been a part of. No doubt he could one hell of a final run with the "team" that made him a Superstar. Another feud with Brock Lesnar would be instant money in Vince's pocket, and awesome to behold for all the fans. And who wouldn't love to see the Olympic medalist go up against new blood like CM Punk or Daniel Bryan - the wrestling matches alone would be worth bringing him back over. But here's the thing: Angle is a pain in the ass nowadays. Every word that comes out of his mouth to press and media is either a lie or a "hack". He hasn't got that much left in the tank, and as good as he COULD be back in the WWE, I just don't think it's worth the pain and/or risk. Plus, what main event candidate would have to be benched to make a return of his caliber possible?
Bully Ray: For whatever reason, Bully (or Bubba) waited until NOW to come out of his shell as a main event singles star. He's good - really good. If he doesn't receive a World Title run in TNA before RVD does (again), I'll be pretty disappointing in the creative team. But the question isn't "who is really good in TNA", it's who I would bring over to the WWE today. Why bring a guy with only a few good years (tops) back into a company that would make him work twice as hard, probably 3x as many days during the week. It'll shorten his lifespan in wrestling, plus the same apprehension about Angle applies to Bully Ray. He's an even bigger pain in the ass to work with, with even less to give back. That doesn't mean I don't like him exactly where he is though.
Bobby Roode: I like Roode. I think he's got the look and skills to get over huge in WWE. But one thing you can learn from the collapse of WCW and ECW is that Vince McMahon really doesn't like talent that gets over without his approval. I'm worried that Bobby is almost "too" good in TNA right now, and as a result he'd have to start all over in WWE. How long did it take Christian to get back on top? Booker never did. Brock did it, but he also didn't leave for another wrestling company - he left and got over in another industry, whose exposure is valuable to Vince McMahon. Roode is a great champion and talent for TNA. It's likely he'd show up in WWE and start from the very bottom. I'd rather he stay right where he is, keep getting better and help further elevate TNA.
D'Angelo Dinero: First he was a big deal in WWE - the next big thing. Then he was a nobody. Kind of like, no pretty much exactly like Drew McIntyre today. He jumped ship to TNA, and almost the exact same thing happened again. He's a very charistmatic guy, but creative teams just can't seem to figure out what to do with him in the long run. I don't really have any faith that WWE will figure it out this time.
Jeff Hardy: In TNA Jeff Hardy's risk is minimal. Even if he gets busted for drugs again, TNA doesn't have enough mainstream influence to really matter in the grand scheme. Why do you think he's still with the company after what happened last year against Sting? Bring him back to WWE, make him work the full-time schedule again and put him in front of 15,000 screaming fans every single night...he's pretty much a time bomb for WWE's corporate image, all over again. I'm also just not a big Jeff Hardy fan.
AJ Styles & Christopher Daniels: There's no way WWE uses AJ Styles correctly. It's taken him a long time to get passable on the mic, and in the ring he's great...against certain wrestlers. Honestly, as good as AJ is, who wants to watch him re-trained, wrestling a WWE-style match? Same goes for Christopher Daniels, except that he's also 41-years-old. The biggest thing they have going for them is their in-ring ability - take that away and make them "tone down" their style until it matches WWE's cookie-cutter approach to pro wrestling just sounds like a terrible idea.
So here's my choice...
Austin Aries. I know, I literaly just said I wouldn't send over AJ Styles and Christopher Daniels because I have no interest watching them work a WWE style. But Aries is much more like CM Punk than he is AJ or Daniels. He can work the mic better than most, and he plays that cocky, tweener-esk heel that Vince LOVES (Jericho, Punk, Bryan, etc.). Austin Aries could work a WWE style and still be entertaining - I'm not sure I can say the same about Styles. He can work with all kinds of people, big and small. He can work a promo about nearly anything you want him to. As a smaller guy, Aries really is the definition of a total package. Five years ago, if the WWE was interested in bringing over somebody like Aries, I would have thought they were crazy. But with CM Punk as a completely over WWE Champion, Daniel Bryan as "Mr. Yes" and other former ROH stars making a debut in the WWE, there's hope. Hope that somebody like Aries could reach the very top of the WWE. Even if he didn't, he'd be one hell of a mid-card wrestling.