Ian Callum said in a TV interview that they released the vert first because it was mechanically harder to design because of the stiffness, moving parts etc (aka solve the most constrained problem first). In the same interview he said the platform was always designed with the coupe in mind also.

The E-type was released in both variants simultaneously ....and the concept precursor to the E-type was an open top racer like the Project 7.

What I wasn't able to figure out when I looked at the history over the summer was: when Enzo Ferrari referred to the E type as the most beautiful car ever designed, was he referring to the coupe, convertible, or the platform as a whole? I haven't found a clear source for this yet.

 

I have the convertible and always get a roadster. But having said that I believe that for some reason the Jag coupes always look better, going back to E Type. Also with roof up convertible is noisy.

 

The F-Type verts and coupes are beautiful IMO but every time I see an article referring to the E-Type as being one of the most beautiful cars ever made, the coupe is the one they always show & talk about.