Suggestion

For context, Minecraft 1.20.1, in case I've missed this feature in 1.21.
We can as of now and to my knowledge sort via config the items via mod order (ingredient-list-mod-sort-order.ini).
What I'd personally like to see is a config allowing to switch the same but with items/fluids/effects as to order them nicely together. For example, if mod A and mod B add both buckets with a mob, manually move them toghether, or with wood types and such. I don't know if it's possible or doable but it would make for a good way to integrate more mods contextually together.

I'm maybe grasping at straws, but an extra category/priority along the lines of JEI_GROUPS to keep convention, and making it so that items with the namespace jei: get all grouped together could be a way to go.
That way, it stays mostly all the same (since, take stairs for example, prioritizing mods would still have all the stairs from a mod on a folder, but prioritizing groups would group ALL stairs onto a folder, then sorting them by mod still) and allows for modpacks to define their own folders.
The only caveat would be that tags would have to have priorities, lest they appear multiple times, but that can also be fixed within convention, via adding another config file like custom_groups.ini where you have something like:

<groupname>: {
    <namespace:id>,
    ...
}

And (maybe, toggleable) the folder icon could be a cycle through all its items or the first one.

Sorry for bumping this issue up by doing this, but I was brainstorming about this and this is what came from it.
As always, thank you for your time.

Hello,

Please see this section in jei-client.ini:

[sorting]
	# Description: Sorting order for the ingredient list
	# Valid Values: A comma-separated list containing values of:
	# [MOD_NAME, INGREDIENT_TYPE, ALPHABETICAL, CREATIVE_MENU, TAG, ARMOR, MAX_DURABILITY]
	# Default Value: MOD_NAME, INGREDIENT_TYPE, CREATIVE_MENU
	IngredientSortStages = MOD_NAME, INGREDIENT_TYPE, CREATIVE_MENU

If you move INGREDIENT_TYPE first, I think it'll look a bit more like what you want.

I am also experimenting with some kind of grouping feature, so that similar items can be shown together, but I haven't worked it out completely.