Tim Leiweke has already been criticized by some in the Toronto media for hiring Shanhan as a way to appease the masses after the end of season debacle.
He might be a newbie when it comes down to running a front office, but knowing Shanahan and how competitive he was as a player, I'd be really surprised if he doesn't approach his new job with the same fierce determination. That he is already talking of making greater use of analytics is just a sign of things to come, IMHO.
That doesn't necessarily bode well for Nonis and Carlyle however. If he keeps them around, I think they'll be expected to turn things around pretty fast.
Shanahan basically takes over Leiweke's spot in the Maple Leafs hierarchy. Shanahan may not have experience at the management level, but his hockey knowledge is a thousand times better than Leiweke's and even Leiweke will admit to that. The decision to create this position was made months ago & the only reason the announcement was made now instead of after the end of the season is because the media had already got word of the potential hiring & the upcoming hiring was already circulating around the league. In order to not put Shanahan and the league in a tough position (conflict of interest, etc), the team decided to make the official hiring & eventual announcement now instead of later.
There is also increasing belief in Toronto that Leiweke will likely leave the organization within the next year. He misses California, he hates the long winter (especialy the recent one) and he's not crazy about the current organizational setup within MLSE since his time there. Let's face it: MLSE might have simply become too big for its own good.
Nonis & his management team (Loiselle & Pouliln) are safe for now. But it's quite obviousl that Brendan Shanahan might want to bring in his own people once he gets comfortable with his new job. But Shanahan will need Nonis in order to learn his job. However, it would not surprise me to see Nonis bolting for the Calgary Flames at any time. Nonis has always followed Brian Burke ever since he first dipped his toes in professional hockey & if Burke is looking for a GM, i'm certain the first name that came to mind was Dave Nonis. If Nonis would ever decide to bolt, it wouldn't surprise me to see either Dave Poulin or Claude Loiselle be named as the Leafs GM for the time being. They are both very capable to do the job.
As for Randy Carlyle, i wouldn't shed a tear if he'd be given his walking papers. He's a very good coach, but he simply isn't a good fit with the current batch of players & it's quite clear that this season, the players were all fed up with him & had tuned him out. The days of playing for a coach the players all hate are a thing of the past. Carlyle has never been a players' coach & I doubt he'll ever change.
Bring on Mike Babcock, who also happens to be a good friend of Shanahan's.