There are a few positives I suppose:
He wanted the job - an easy retort here will be "of course he did! £6m p/a" etc., but it's also true he immediately distanced himself from other club management positions since he left Palace. He wanted to be the manager of Everton because he sees us as a big club, the kind of club he's wanted to manage all his career (Newcastle and WHU are not in our stratosphere).
Again, this might not seem like much but it's certainly preferable to a guy telling journalists that it's his dream to manage Barcelona or that Lukaku is too good to stay at Everton. Despite being 63, Allardyce will still feel he has something to prove and it's here that he has the opportunity to do it.
He can work with our DoF - Walsh is immensely unpopular here, I know, but we have to accept that Moshiri is giving him more time in the role. With that in mind, we obviously need a management team that can work together successfully. This appears possible with Allardyce (and Shakespeare to some extent I suppose). We can claim cronyism, of course, but that doesn't necessarily negate a successful working relationship. I know this point will be very quickly shot down - and I'm not particularly sold on it myself - but I'm willing to see what happens in the next transfer window before I form a real opinion.
Defence and tactics generally - our last two permanent managers were sacked when it appeared that we were tactically void and a shambles defensively. This new management team - and I'm pained to include piss-stain Lee in this - has a track record of developing tactics that get the best out of the talent available to them. There are negatives here as well, of course, but, in a thread where we're looking for positives, it's fair to say that this is the biggest pool of talent and resource that Allardyce has ever had, albeit an uneven one. If he is able to drill our defence, select a team that play to the strengths of the personnel, and make the necessary recruitment in January - all things he has shown he is capable of doing - we'll see an upturn in results.
As I said, there are plenty of negatives - including what I think is a main one: it's a deeply unfashionable appointment that makes us look small time when we have been anxiously wanting our status and public perception to appear big time - but I don't think any of the above is untrue, either.
In the kindest light we can shine on the desperate public mess of the last six weeks, this appointment might offer 18 months of careful and considered stability during which a more ambitious and progressive recruitment process can be completed. This happens at board level, with a proper CEO and an owner who is present and has a clear and ruthless ambition.