Giving flexibility to re-order the categories is a good idea so I am not against it as it gives us flexibility.
However, ordering them by the order of importance you associate with them may not be something the end users relate to.
I would have thought alphabetical is a good (if not the best) choice as it makes it really easy for the end users who are entering the feedback to find and pick the category they are looking for.
Of course, if end users are not your focus....not sure why you even have a feedback portal.

I want to be able to set the order the forums show on my portal.

If you use multi-digit numbers for the title of Labels and Categories, they do not get sorted numerically. (only the first digit is used for the sort order)

screenshot: https://cl.ly/3F1M2H2P2D3D

I would also like to have this functionality.

This is really important for me too. Please add this feature.

I would also love to have the option to organise our forums. I'm also using numbers in front of the name but it looks a bit naff! Look forward to seeing this one day soon.

We also have an urgent need to sort the forum list. In particular, since a forum can only have ONE language and we support twenty in our service, we want to be able to group Spanish Translations and French Translations etc. into one group, but not have that group be above other general interest forums. A quick fix would be to allow Admins to prepend a non-visible character string with a sort order, such as ::01:: Forum Name, and ::02:: Forum Name.

Agreed! Forums should be able to be placed in order of importance, not just alphabetical. I made this comment here as well - http://feedback.uservoice.com/forums/1-general-feedback/suggestions/3168341-enable-the-forums-to-be-better-organized-not-ju

Why can you only organize the forums in alphabetical order? I'd like to present my forums in a specific order, since I'd like to give some forums more attention than others. I tricked the system by using numbers in front of the forum name, but that only works for 1-9. This would be a great improvement!

The ability to order categories based on importance is essential and should be added. Thanks!

Alphabetical is practically arbitrary on a list like this. Please allow the ability to order the list however an org sees fit. Thanks.

It would be nice if Admin could manually choose the order by moving items up or down.

+1