Category Filters order should be separate from Category Display order.
Currently there is only one list of categories that controls both the order of how the Category Filters are applied and the order of how the Categories are displayed in the Bags UI.
However, the Category Filters order is typically forced by necessity - in order to correctly assign the categories the more specific filters must be run first.
On the other hand it is natural for people to have [different] preferred display category order.

Describe the solution you'd like
Proposed solution:

1. Add separate config page 'category order' in which the user can drag the categories up/down to specify how they should be displayed.
2. Add a toggle on top of the page "Use custom category order", False by default.

Describe alternatives you've considered
I don't think there is an alternative.

There's a priority slider

OK, if you change that priority slider to have 100 instead of 5 values that can be a workaround. Not as user friendly as a draggable list...

Its worse to require having a list to arrange to sort which item goes where though.

You'll find that most categories don't clash and don't need prioritisation, so you can safely ignore the slider except in the few edge cases where it matters.

If you have a specific example which can't be solved by moving the priority sliders I'll look into a different solution.

I do agree that I should be able to achieve my goal with the current interface. I felt that changing the priority slider to have more values should be easy and useful change, so I suggested it.
Here is my use case:
My real goal was to create separate section for each equipment slot, and I want these to be on the top of my bag window. So, I created group with filter "chest" and found that it included not only chest pieces but also chest enchants, so I realized I will need to move the category for item enchants before the equipment categories - which led to me creating this 'issue' here.

That's got a different solution, any of the following will work:

1. Use the Group by option on a category
2. Use the Inventory Slots (Auto) category
3. Prefix chest by # so it only does a keyword match and not an item name match

Thank you for the help!