For general admission shows, do they let you wait inside during winter months? Or is there a wristband type of situation, where if you get there early enough, you can come back in a couple hours? I've never seen anything here.

They let u in an hour before the show

Went last night to see We Will Rock You. Only line was to go through the bag check which was short and then I went immediately to my seat. I arrived 45 mins before showtime which was enough for a restroom and concession visit.

you have a large area. Kind of a comments area before you enter to the lower landing and seating area. Large enough to fit at least 2500 comfy

Its both ...and depends on the concert for general admission you wait on the line even if its snowing...if you get there early that side of the line will be inside hulu theater has an email for guest questions too