-Internal restructure of the game to be more data-driven, up to modern standards, and easier to use.
-Cleaning up, optimizing, and reorganizing ancient code.
-Datapacks to evolve past being command packs and using the fact that the game would now be data-driven, allow the implementation of entirely custom blocks, items, entities, and more with their own tags, e.g., "mydatapack:customblock"
-Minecraft itself being a datapack within the game so it can be disabled and replaced with entirely new experiences.
-Scripting API within datapacks, using a custom Minecraft language so Mojang can offer extreme functionality while not having your computer at risk. Having a
powerful scripting API would allow mods like Create to be ported to datapacks.
-Consistency with crafting with blocks like stone, deepslate, and granite. These 3 blocks alone have extremely different ways to craft their variants. STOP.
-Overall optimization.
-More Block Shapes. These arbitrary limitations are just that - arbitrary. Say what you will about "being creative" but vertical slabs at the least are a necessity. It's a slippery slope, Mojang, and you made the decision.
-Bring back the otherworldly fantasy vibes. World generation is nice, but it doesn't capture the same wonder as some of the older versions. More out-there mobs, blocks, items and more is what Minecraft needs more of. Minecraft is not real life.
-More unique weapons, items, and blocks, e.g., chains, the mace, the trident...
That's what I want for Minecraft mostly summarized.