I made my cloud 2"...made that decision by reading on here...plus it would have too heavy if i made it 4" It weighs 50 pounds and is 6'x6'
Your room is almost exactly the same dimensions as mine....
Yes, a cloud is an early reflection point....and you can find it with a mirror...although i plan on just centering mine in accordance to my bass traps mounted on the ceiling corners...its big enough that it will catch all the early reflections..
some say that the cloud just need to go as far back as the end of the last sidewall 1st reflection panel. But i wanted mine to extend completely over the listening position since my room is really live.
i asked the same question about how low it should hang, and ethan told me 2"-6" The higher up the better though..this holds true for room size as well.....the longer distance the sound has to travel before it strikes an object the better.
I cant tell from the pics, but it looks like the ceiling is just slanted not vaulted? if its vaulted, then i would assume the two highest points meet in the center of the room and extend the length of the room?...if thats the case then just center the cloud in between the corner point of the vault....but really the pics give impression we are talking about a slant here...
anyways, i would just have the cloud covering you and the speakers
heres mine ( LED lighting optional

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