Larger lenses are easier to put together without distortion, but the are all pretty darn good. There are more factors in light transmission ( presumably for shooting in bad light ), than just area of glass.
- glass quality
- grinding
- coatings
- matching lenses
- true coloration
- resolution
I have a 1.5-6x42mm 30mm tube scope with 91% light transmission. I have, and have had, 35mm and 36mm 1-inch scopes with 95% light transmission, which looked very bright. What that 30mm does have is huge field of view and 5-inch eye relief, which makes it great for fast shooting at driven or charging game in the woods, especially on a .444 or .375 H&H.
A high quality scope with terrific resolution and true coloration, like a Swaro 3-9x36mm, will let you see detail in poor light which a larger scope with less resolution will not. You cannot just compare them on paper. You need to compare them in the various light in which you shoot, on your rifles, and on the game animals in that light, with their hair.