I didn't read the sixt pages of this, but here's my personal view on the original topic.
Personally, I prefer groups of three, or AT MOST four, to do most events.
I have logged out before large scale event like wars and such (even though my character would absolutely get involved in this as it's a part of him), because I can't stand to see 6-8 PC spamming my chat window. It gives me headaches.
Also, I like taking it slow. I don't like when somes are always running forward, doing things ahead of the rest of the group. I prefer to go slow and learn who everyone is, or learn more about those characters you already know.
I do not willingly set aside people because I think it's rude, but I sure as hell don't like it when there's more people than needed.
For the plots, I prefer when it's shared when it should be. To keep it real.