Auto tile texture

Hi all I am making a 2D platform game and Im having problems using repeated tiling textures on my 2D quad scenery, I have created a unlit material with a texture and have set the texture to repeat, I understand I have to set the tiling x and y in the material, but I have a problem in that my scenery is of varying sizes, and I don't want to have to manually set the tiling for each quad.

Furthermore I don't want separate materials for each quad as they may be potentially hundreds of them and memory would become a big issue. Also I need the pixels per unit settings of all my sprites and textures to display consistently as they are in photoshop so a 50x50 texture would be a quarter the size of a 100x100 sprite ect ect. is there anyway to achieve this ?

Many Thanks !