The idea of a Tibia-mu map is good, but to be honest, the map lacks atmosphere. Many sprites need to be changed, and decorations added. There are many servers with excellent sprites that could be used in this project. I would start by completely changing everything, from the ground and grass to the trees and even the mountains.
It's a good project; just improve the environment with better sprites, and I think the map will look more vibrant.
Good luck with the project.