Roger Hicks
Veteran
Ilford Advocate. . . Additionally, if innovative exterior design matters, I'd say: . . .
Alpa 12-series (not just external innovation)
Mecaflex
Gandolfi Variant (again, not just external innovation)
Various "Art Deco" designs from Agfa, Pontiac and more
Early Periflex (pigskin cover)
Mick-a-Matic, especially the early ones where Micky's ear was the shutter release
The Leica Luxus is too well known to mention here.
Cheers,
R.