I am about to start to developing backend site of a php project. Companies and site admins will login to this site and manage their data on the project.

My previous admin panel experiences were full of agony and pain. So I want to make sure that I choose correct tools for my purpose.

By the way, please note, I'm not looking for scaffolding. There won't be much tables in my database. Instead, there will be complex logic between entities.

I want clear seperation of markup and logic code and easy-to-use and standardized user-interface.

Thank you.