I agree with the all your similarities except for the Elite armor Choot. Good connection though! Alright if that Forerunner symbol is the same as the one that AC's been passing around, according to this:
http://www.halopedian.com/File:TerminalDecoded.jpg
The symbol most closely relates to the symbol for "ᴭ" which is latin from what I've been coming up with on google.