I know you have already planned to improve the separation of the textures, but as there weren’t a ticket about this, I decided to create one eith some other things related.
So as you know, there are only 4 sections for the textures. Blocks, Items Armour models and Others. In the "Others" section, there is entity textures, GUIs textures, mod logo, everything that isn’t a block, an item or an armour model. In my opinion, it will be better to separate all of the texture types in several folders, like, blocks, items, entities, potion effects, GUIs, etc. You can keep the "Others" section, but it will contain only the mod logo and textures like it. The same folder type for custom sound could be implemented, but instead of blocks/items/etc, it could be musics/jukebox/ambients/passive/hostiles etc.
I don’t know if this one is not enough related, but I will make another ticket in 48 hours if needed. The possibility to create our own folders into all of the ressource elements (textures, sounds, structures and 3D models) will be very nice.
These two feature will improve the organization and allow to make a better Resource Packs Generator and to change Vanilla structures inti the Data Packs because Vanilla structures and textures need o be into specific folders.
P-S: If there is already a current ticket for this feature, I’m blind because I did a lot of research as it was already asked.