The Golden Age of aviation was great. The developments that took place in aeronautic science that translated into changes in the way designers thought about what they were puting in the air made it a tremendously significant time in aviation. It should be given more respect by the model manufacturers.
Personally, I think a 1/48 or 1/32 DeHavilland Dragon Rapide would be great.
A new Stinson Reliant kit would be good too.
A trully historically significant aircraft that I think has been overlooked for too long in kit form is the Dornier Wal. The type played a significant role in navigating routes over both the North and South Poles for the first time.
When you ride on an airliner and realise that the routes they take to get you from here to there were established in the Golden Age of aviation by folks who had no less daring and zest for adventure than other great explorers like Henry Hudson, Lewis and Clark, Christopher Columbus... and took very similar risks in opening up new ground in how we get around this world of ours; why, when there are kits of Columbus's ships available, are there not kits of some of the great aircraft of airborne explorers?
I say an emphatic "Yes!" to a 1/48 Vickers Vimy representing the transatlantic flight of Alcock and Browne.
"Yes!" to a decent 1/48 or 1/32 Spirit of St. Louis kit.