I agree with keeping it simple, if you don't usually wear make up & dont want to then I wouldn't put much on.
If you dress neatly etc & neat appearance it shouldnt matter....unless you are at a front desk & are the first impression of the workplace, then I might put more on.
Again I agree with a tinted moisturiser..they work great. Mineral makeup is great also, just dust over the powder to create nice even skin tones. Some mascara & lip gloss that you can keep in your bag & apply as needed during the day.