why gray?

white gloss subway tile, polar white sheen cupboards, no overhead but p/white open shelving and organic white ceaserstone bench tops. Walls are a light grey with white architraves & skirting boards. Wanting grey grout as have had white in the past with similar but larger ivory tile. Not sure how light or dark a shade to go? looking at pros/cons for blending or featuring, cleaning etc

Thanks Devon, going with white tiles but want a contrasting grey grout