Re: Do what I've done
Innocent question: I know there is a LOT wrong with Win 10, which is why people have to be nagged into upgrading, but what is wrong with iOS upgrades?
There are two big issues:
1. Time: to do the upgrade you really need to confirm everything has been backed up and that there is space on the device in which to perform the upgrade. Basically, I've there and got the t-shirt too many times to know that whilst an update should run without problems, it is better to allow for contingency, just in case you have to either recover the system or press another one into service (whilst you recover the failed device). So I usually delay doing a version upgrade until a convenient time - for both the regular user(s) of the device and myself.
2. With iOS 9.3 there have been many reports of the update failing on iPad2's, with a problematic recovery. Hence it has been sensible with these devices to wait; 9.3.1 doesn't attempt to fix the iPad2 installer problems, so it may be advisable to wait until they do... But this is really just a special case of point 1 above.
So fundamentally, the issue comes back to time management, the value I place on my time and where installing updates fits into my priorities and schedule.