I agree with Dpreston about seeing the colour in person.
396G is actually 'medium blue' - I think you might be lured by the fact that 396G is metallic colour whereas 332G is solid.
I once read on the forum that a survey of the most desirable combination was Midnight Blue 904G with parchment interior.
I am a purist and swore never to change an original colour (and am 3/4 way through a nut and bolt restoration in it's original colour of Dark Red) ……..but I have now weakened, and would entertain the thought of restoring a car (future resto) in a preferred colour. I love Anthracite or Beige Grey - my friend has a stunning Moss Green car...…..I could go on.
I also feel the change in colour (as long as it is one of the more desirable colours) has little impact on the value these days.
Of course, I would have no qualms about changing the interior colour.
I have 3 Pagoda's and love them all but my 906G Grey Blue is the rock-star that turns the most heads. It is it's original colour with an original 2-tone darker Blue roof/Hubcaps. The original interior was blue vinyl but it had a cream interior when I bought it. I restored it with parchment leather interior as it looked nicer. I'm also partial to two-tone colours.
For mine - go with your preferred colour but look at the cars in the flesh first (5 years ago I would shot myself for saying this).
Also bear in mind colours look different under different light - especially the metallic. (see attached - same car in each photo).
p.s- I agreed to let it be used in a wedding shoot - I don't actually know them
Good luck! Would love to hear and see your final choice!