I found some time to work on my tree product.
I'm finally done creating the 100 tree object, which all use the same UV mapping.
I also created about 20 different textures to change the leaves of the trees(100 objects x 20 UVs = 2000 different trees).
I still want to do some more textures before I release the final product, but I hope to release a first version soon.
The idea of this project is to be able to change all the trees(or groups of trees) of a scene by changing a single texture in a material.
Also the blender file has a multi-cam setup to create renderings of every tree that can then be used in 2D game designs or as low-poly background decoration in 3D designs to reduce render time.