Blush and eyebrows!
I wear makeup to the office very day because it makes me look a little more polished, and feel more confident. I pretty much never wear lipstick, mostly because I can't be bothered to touch up. I stick with a lip balm, so the effect is very low contrast, but the moisture content the balm adds brings more polish to the look.
Anyway, my recommendation for makeup for the office is always blush and eyebrows, which, if done correctly, brings a lot to your face without looking like a lot of makeup. If you're feeling pale, a bit of blush or bronzer can help you feel much better. And doing your eyebrows means you can pay less attention to mascara, eyeshadow, etc, if you don't want to.
That said, my office makeup routine is BB Cream, mascara, tighlined eyeliner, brows, blush, and lip balm. Most people comment that I never wear makeup, even if I am, so it is all done with a very light hand.
P.S. - can we just marvel at the number of times I used the word "polished" in that post? I usually like a more RATE look, but not appropriate for my office.