Agreed. Hell, even the more crazy theories from /co/ like somehow Amon is an ancient Air Nomad survivor, or had at least Air Nomad ancestry making him a Magneto expy of the Avatar world sounded way more interesting to me than he just some abused OP bloodbender who used his OP ability to somehow cancel a person's ability to bend. He could have had a connection to chi-blocking.
Amon dealing with the Spirits to attain energy bending could have been a great set up to all the things that followed in the setting. Air benders returning, weapons of mass destruction via spirit energy, the relationship between spirits and humans attempting to co-exist, or even having human in spirit form that counters the Avatar. It all sounds cool, and it all looks it can connect, but it doesn't. It's all a disjointed mess.