Resource Packs
Texture and resource packs worth your load time, with side-by-side looks at what changes.
Five resource packs that make vanilla Minecraft 26.3 look better, all with a release for 26.3 and none of them needs a mod or OptiFine: Better Lanterns, Round Trees, OS' Colorful Grasses, Faithful 32x and Fast Better Grass.
Lanterns and chains get detailed 3D models, and copper lanterns are covered too. A plain resource pack for Minecraft 26.3: no mods, no OptiFine.
The classic Minecraft look at double the resolution. Faithful has been around since 2010 and is already updated for Minecraft 26.3: no mods, no OptiFine.
Grass blocks turn green on the sides, like OptiFine's Better Grass, but as a plain resource pack. Paths, podzol and snowy grass get the same treatment. My number 1 for Minecraft 26.3.
Plain grass turns into bushy tufts in different shades, with pampas grass in between. A resource pack for Minecraft 26.3, no mods and no OptiFine, with a short version too.
Square tree trunks turn round. A plain resource pack for Minecraft 26.3, no mods and no OptiFine, and it belongs at the top of your pack list.