MU-TH-UR’s Super Mario 64 Texture Pack is a solid effort at retexturing Super Mario 64. Using a blend of somewhat semi realistic and cartoony textures to create an interesting feel.
This texture pack while incomplete does manage to cover the vast majority of Super Mario 64 with the texture pack being about 70% complete. Sadly Razius decided to stop production of the texture pack in favour of his work on texture packs for Super Mario Galaxy and Super Mario Sunshine.
The main reason for this is that he just greatly prefers the way Dolphin handles texture creation.