5th Edition D&D has a skill problem. It lies in a feature called expertise, which allows you to add your proficiency bonus twice when using a skill. Let's see what problems this causes and I'll give you a simple hack to fix them!
Reliable Talent makes all your skills passive. In order to see what you're really getting from this class feature, you need to find out what skills already function passively, and what skills only function actively. We'll examine passive skill treatment in the rules and analyze where each skill should fall.