More customization for everyday vanilla items. Stuff that could be used to distinguish factions. The armor trims are a wonderful example of this, as well as banners. I'd like the banners to be able to be flown sideways, like actual flags. Maybe some customization for boats as well. Tools even? (I know that one's probably already been suggested because of the armor trims). Elytra trims or just something to make it unique to the player!!
I remember when Pokemon first came out with the character customization options. I was always broke in that game because I was always buying new outfits and stuff! I just want to make my character more.. ME. And also! Think of the role playing aspect of it all :D
If I were to make a list:
- armor trims (got it already, but it counts)
- weapon customization, maybe with shapes instead of colors?
- the ability to put banners sideways
- ability to make banners larger (maybe 2 or 3 x larger, not something crazy giant that could've just been built out of blocks)
- ability to put banners on more things like beds, the flanks of horses/camels/etc, maybe also attach them to signs so they can hang from the bottom, underneath the sign
- boat trims or ability to put banners on boats as a mast
- elytra colors/trims or banner patterns being compatible with the elytra design
- more banner patterns and more than just 6 (or is it 7?) layers
- custom written book cover colors, maybe with some patterns/designs for the covers to have more than just 1 color. This could be like an in-game version of a wax seal stamp for messages between factions/kingdoms!
- maybe also the ability to customize a goat horn to play a series of noteblock notes, maybe a maximum of 6 or 7 like the banner (or more if they were to be expanded upon). We can make our own kingdom anthems/jingles. Maybe this could be done by giving the noteblock a GUI where if you shift click on it and insert any goat horn, then press note buttons it'll play those notes every time the horn is right clicked. Sorta how Animal Crossing New Horizons did it
- ability to combine the aesthetics of one armor set with the stats of another. The leather armor and its trims would undoubtedly look really cool, but are super impractical to use late game, especially if pvp is a thing on the server, and a war breaks out lol
- ability to customize the GUI color and style of readable books. Imagine having a curly royal purple page background for the royal decrees of law and order of your kingdom, or having an Egyptian looking page for a desert king's last words before he mysteriously perished. Or simply a beautiful layout and color for your diary
- shulker trims? lol the trims are really cool and honestly I'd like to see more of them
- ability to dye redstone lamps (this was probably already suggested a loooong time ago, but fits with this theme)
- let villagers wear (at least leather) armor so we can have our npcs in the kingdom look like they belong by wearing the kingdom's colors. Additionally, this could help sort trading halls by color
- maybe let us have a vanilla way of coloring our names in chat to show allegiance to a group, or just for coloring it our favorite color
- maybe icons next to our name if we enable it in the settings? not sure how it would work exactly...
Also, just want to say that I'm not saying that each and every thing in this list is necessary. I'm just spitballing here.
