What I don't understand is the motivation. We know that money's not the main driver or else he would have gone to Barnsley. I can only guess then that he wants to manage on a bigger stage.
As it stands the way this can be achieved is: do well in Scotland -> go to championship club -> get promotion to the premier league
The question then is, where is Butcher most likely to get a move to the championship from and how quickly is that going to happen. We know, from the Barnsley affair that his success at Inverness got him an offer so there is no impediment to a championship move from his current role. Hibs are a bigger club but will take time to turn around and there is no guarantee if success, this seems to be a high risk long term path to get there. The smart move is to stay where your stock is high and the team is performing well, that will get him his championship move in the shortest period of time.