I'll bump this and maybe help get the conversation going.

First thing: Full size sheet pan is 18 x 26. Have you tried measuring with your tape measure?

Second, 18 x 26 is what I recall being the interior dimensions of the oven in the 30" BS RNB I saw weekend before last when a friend dragged me along on her stove shopping expedition. Seems like the full sheet pan would be tight, though maybe not quite as tight as on the other stove you looked at.

Also, 18 x 26 is a "nominal" dimension for a full size sheet pan. There may be are slight variations between brands depending on how canted the sides are and how they roll/reinforce the rims.

Maybe somebody will have direct experience with a full-size sheet pan in a 30" BS? I know BS says you can put full size sheet pans in the ovens of their 30" range, but. I suspect you would get very uneven baking when you do that in the oven of a 30" model. But, again, we need to hear from somebody who has actually tried it. I only know about doing that in a 36" range. That wider oven gives space for air and heat to circulate..

Perforated pans? We used to use them for certain breads, such a hamburger buns, but I've never tried one in a 30" oven. Seems like you would have the same problems with a bun pan as a regular pan if you fully load the pan. If you aren't going to fully load it, why bother with the really big pan?

Full size wire cooling racks would not block the oven the way the sheet pans would. I've only used them for dehydrating. Tried roasting vegetables on one once, but some of them (such as zucchini) stuck and made the rack hard to clean.