I am not sure exactly how formal your workplace is going to be, but I would also consider wearing the black pants with the grey jacket and vice versa, as well as buying one or two nice cardigans in your neutrals, so you can combine those with the pants/skirts of the suits. A little structure will also help add visual interest (a knitted detail, a structured bag).
I also wholeheartedly agree with wingatprsct: get some (affordable) tops and blouses and inject some color in your wardrobe. If you're on a budget (aren't we all these days?), it's easiest to choose to have either neutral-colored printed tops and skirts and brightly colored accessoiries (bags, shoes, jewelry) or vice versa. I tend to opt for neutral shoes and bags and go for brightly colored tops, because nice shoes are not a afforadable as tops where I live. Also, I need some color near my face, or I tend to look washed out.
Good luck!