Looking real clean bro. It's got a lot of potential!
As for the numerous items you mentioned you may be changing, I just thought I'd add my opinion to see if you value any of it haha
Whilst I don't think Calais grills look as good in white VS' (compared with the other colours like silver, green, etc) they still would be a nice addition to yours if you wanted some on the cards. They aren't too hard to come by but they're pricey for what really is just a piece of cosmetic plastic
as for the colour change on the plates whatever suits you, don't change just because others don't like it! If you really were thinking about changing, white on black/black on white looks decent.
Interceptors would look more pleasant than your current rims, but then again it's a calais. You should go take a look at and perhaps consider some WH Caprice rims or even the stock S2 Calais ones polished! They look classy and tidy!
Either way dude, it's a good find/swap you made!