It amazes me how little the USPS "clicknship" website has changed over the past 10+ years. A consumer still cannot go online and print out a stamped, first class envelope, let alone an unstamped mailing label. You still cannot fill out paperwork for certified or registered mail online, instead you have to go to the post office and scribble on one of those adhesive-backed green labels with smudgy ink. If you don't want to verify a mailing address or ZIP+4, it's far easier to type it into Google.com than USPS.com because you can't do an unstructured search for an address without tabbing between Address1, Address2, City, etc. Unless you're sending an Express Mail overnight package, there isn't much you can do from USPS.com.
The USPS need a leader who can really embrace technology, deploy more online self-service tools, and more functional self-service kiosks. Maybe they should just buy out stamps.com for a billion dollars and offer it as a free service to everyone.