A) Colo is $50-150/U with blended top tier bandwidth, 99th% billing and usually includes remote hands time.
B) Even with 100% redundancy you're still ahead by $3000/month. Please understand Amazon offers absolutely no redundancy built in and nodes go down regularly. It is up to you as a developer to build redundancy around the tools they offer.
C) Amazon doesn't take backups for you. You have to pay for this either way.
D) Again Amazon doesn't handle this for you. You have to pay either way. Buying an exact replica of the hardware I've mentioned and cololocating it elsewhere still puts you ahead by $3000/month.
E) What support do you need? Dell offers same day or even 4 hour parts replacement with the appropriate warranty service. Most Colos offer remote hands for free up to a certain hourly.
F) Lots of ways to handle this. You can use IPMI, built in OS tools, etc. There isn't much exclusive to AWS you can't easily replicate elsewhere.
G) I never said not to use Amazon for anything. In fact you should be building your applications for scaleability INTO the cloud. This is part of the idea behind the whole microservices movement.