Oasis class and Quantum class probably have the most shows. Ice shows are also available on Voyager and Freedom(I think) class. There really is no best.
We don't pick a cruise based on the shows.
As I remember there is an inside hall where you wait in line if check-in hasn't started. RCI doesn't sail from Boston all that often so it depends on the training of the contractors.
I'm against anything that would put more passengers into the Lounges/Clubs.
I'm sure there are Pinnacle passengers that get an exemption for their guests.
GSs on any Radiance class are not under the Windjammer, except for 1600. You may occasionally hear pool chairs, but it's not bothersome. 1600 is a disaster, you'll listen to chairs scraping the outside Windjammer deck all day.