The ordering of categories - manual or alphabetical - should be a blog setting for the individual blog. It should not be a setting for all blogs in one b2evo instance.
So I could have blog - like the link lists in the sidebar - where the categories are sorted individual. And in the other blogs the cats are sorted alphabetical. This would be very nice.
Or better: I could decide in the widget - e.g. categories, simple link list - how I want to sort the categories. So I can sort it in the widget categories alphabetically and in the widget simple link list manually. That would be great. ;)