Eberron's new Changeling is the first class that can start with an 18 ability score at level 1. Although this "power creep" doesn't mean the class is unbalanced, the answer to rebalancing the race within the existing design paradigm may lay within cut content.
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.