Shane's return, this time around was reportedly agreed upon a few weeks ago and although he is playing for power on screen he does not hold a managerial position with the company at this stage, but that could always change.
In a twist of storyline meeting reality, Shane legitimately felt he would be the 4th generation McMahon to run the WWF/E but his Sister Stephanie had surpassed at the time due to her "product knowledge," something which a lot of people knew at the time but Shane. Vince had to inform his son at the time that Stephanie and Triple H would be running the company, which ultimately lead to a real-life family rift and Shane leaving his CEO position in 2010. There is said to be a "significant amount of life imitating art" in what Shane said during his promo. Apparently there's is also a belief that a real-life power struggle will occur if Shane's fully back in the picture backstage.
Melzter also noted that while Shane might be well received on screen with fans hoping he takes "control" of WWE, in real life people wouldn't be as receptive to Shane if they knew about his booking ideas, this is why Vince went with Stephanie running the company and not him. He claims that "almost everybody that I know personally liked Shane over Stephanie but, when it came to ideas when it came to wrestling, when it came to wrestling angles, it was Stephanie and Paul (Triple H) are so far ahead of him that it's not even funny
Source: Wrestling Observer Live, Dave Meltzer
The way Meltzer worded that really does make me believe Shane McMahon will win at Wrestlemania and get control of Monday Night Raw. There's gotta be something screwy happening, though, because there's no way he's beating Undertaker without outside help.
As far as creative, I can't speak about Shane, but we know Triple H is so far ahead of everyone else in the family creatively that it's not even close.