I'd agree that a mage portal to Shatt takes care of most day to day needs, and it is the far off places that are a pain.

Think in terms of travel time; where do people go before 30 (without a mount), where do people go mounted (that still takes forever) Kargath and Silithus are top in my mind even with mounts. Gadgetzan was the worste walk, but might not be needed before 30 anymore...