Hi Tamara,
sounds like you have excellent taste too Our main floor tiles are a light greyish/neutral colour, our bathroom/ensuite tiles are a darker grey, and we have grey & charcoal glass feature tiles in our ensuite with glass feature tiles in our kids' bathroom too but with a hint of colour in them (grey/brown & aqua blue). Didn't end up finding any charcoal carpet at our local floor covering store and because I couldn't be bothered going out of town to find something (and time is running out) we've chosen a lovely black carpet. Hoping its not too harsh but I think it should be fine. I absolutely love the pattern in the carpet pile, and best of all its one of those that wont show the vacuum tracks.
Anyway, our kitchen is also white - Caesarstone "Nougat" benchtops with White gloss doors that have a hint of sparkle/shimmer to them (colour is Galaxy Pearl Gloss from FlexiPress). Its all being put together on the weekend so I'll be able to tell you whether the walls look blue. At this stage I don't think they will because we picked up the doors this afternoon and have them all stacked inside near the walls and no blue tinge it seems. I'm so glad we did the final coat of paint in Lexicon 1/2 though. If you're going Lexicon 1/4 you should be absolutely fine.