I may be out of sync with many, but I just don't get all the angst on this. Replacing any member of staff is a tricky process, let alone something as crucial to a football club as a manager. Why do folk expect it do be done quickly? I'd much rather it were done right.
There's so much we don't know about what's happening behind the scenes, who is available, who is not. It's not as easy as simply having identified a few names beforehand and then them magically being in a position to say yes right off the bat.
Apart from the Cup (which is a long-shot given the state of the team) this season is basically a write-off now. So far better to limp on and get the "right" person than do something quickly.
Even then, there are so many variables that the "right" person may not succeed. Most managers fail. Even if the "right" person says yes, there are wider factors. I don't think it would be too speculative to suggest that Jimmy not bringing his family with him had a negative impact, as did the loss early on of a key member of his coaching staff.
Life is full of shitty variables that mean the best laid plans o' mice and men gang aft agley.