I am a customer of packet's, along with other virtual and dedicated hosting providers. I don't use aws ec2. I've been pleased with Packet, and their offerings are much more diverse than this initial offering from aws.
The location nearest me is an "edge", not a "core". I wonder what I would be missing out on, if it's not "core".
Even in core DCs though the availability of different types of machines varies.
Love packet.net btw -- the bgp stuff is really game changing.
packet.net I do coreos and provision with userdata specifying what docker image to run... that's all it takes to have immutable deployment :)
Building a high-availability metadata store is not easy. And ensuring that incoming request IPs aren't spoof is a little non-trivial to reason about.
UserData is a good way to provide a one-time token that can be used to fetch data...
Using SSH for provisioning is just plain dirty... and almost impossible to do reliably... You'll need global locks and timeouts to recover in case one of your master crashes... Plus some garbage collection to cleanup things that where not fully provisioned.
This is a LOT of unreliable state to manage. And ton of corner cases. Having the right architecture matters for reliable automation.