Note: This is verbatim copied from my post on Minecraft Feedback, Microsoft's official titular website. If you'd like to help Mojang/Minecraft notice this suggestion, you can proceed here to vote for the suggestion. Otherwise, this thread is mainly meant to display the concept and open discussion of the concept within the PMC Forums.

Colour Tags and Description Tags

As alternatives to Name Tag items, there should also be Colour Tags and Description Tags. This would allow a Survival method of editing more data for items and mobs than just their names.

Colour Tags
Effects on Items and Mobs are interchangeable

Colour Tags change the colour of an item's or mob's name. Colour tags are white (or "reset") by default, and can have their colour changed by being combined with any dye in an anvil. Colour can also be stripped from a Colour Tag to reset it by combining it with a Water Bottle in an anvil, which will use the water but retain the bottle.



Description Tags
Function

Description tags are edited in a book-like format, allowing 3 lines of text to be added. The colour of a Description Tag can also be alteredby combining it with any dye, and is light grey (or "reset") by default, and applies to the same dye functions as Colour Tags.

Effects on Items

Descriptions will be applied in the standard item description area beneath its name.

Effects on Mobs

Descriptions will form extra lines beneath the mob's name. If the name is default, it will simply say the mob's default name (e.g. Zombie, Ghast, etc.).

Whether or not these items (alongside Name Tags) are craftable are up to Minecraft devs, though crafting recipes for these items would be nice.