This is approximately the same level of detail that I try to give when I'm writing to United to request compensation. I think the main issue is that you have so many distinct (and legit) complaints; I concur with jsloan's suggestion to separate the return flight from the outbound.
That's fair; it may not look like too much detail when split into separate messages.
Final note: IIRC, what happened to you isn't technically an [involuntary] downgrade. United promises to get you to your destination in your purchased class of service... but they do not promise to get you there in a timely fashion.
This is 100% correct. From UA's point of view, OP volunteered to be downgraded in order to get to India faster.