Was just gonna say regarding difficulty between 8m and 16m. People's opinions seem to vary on this, but the devs said something like:
8man the content itself is harder in the sense that say damage incoming is X. And enemies health is Y. And you have 2 healers, 4 dps, 2 tanks etc.
Where as in 16m, you have 4/5 healers, 2/3 tanks, 8-10 dps, and instead of Damage incoming being 2X, its 1.8X, and enemies health ebing 1.8Y instead of 2Y. (As in its not exactly 2 times harder, despie having 2 times as many people).
However MOST people who have done 8 and 16 will probably say 8 is easier because coordinating 16 people properly is a lot harder than 8. And all the coordination etc makes up for the slightly easier 'numbers' in 16man. And theres also space, as in on 8man youve got lots of area to move are, dodge void-zones blah blah. In 16man things can get a bit tight, and small mistakes can kill more people.
Thats how I see it anyways
The only fight I've found harder on 8man is Soa, he is a real f**k face on 8man nightmare lol.