Well, first of all, you had solid and diverse experiences. It is impressive.
Based on your experiences, I guess at least you have some idea what you like and what you do not, what is important to you and what is not. In this fast paced world, it is hard to plan it all out. Most likely you have a direction and have to go with your gut. On the other hand, if you know your heart is not in academics, don't do PhD. If you are still not sure, explore more.
I am not sure what is your age. AFAIK, most PhD in business are in their late 20s and early 30s. I guess only the lucky few know what they really want in their early 20s. Most people have to experiment and find their path in life. It takes time. I myself is an explorer and am not that young. Time may no longer be on my side, but I am getting wiser and closer to finding my path in life. Hope the same is true for you.
In short, question yourself, relentlessly, is academia where you belong, or somewhere else? Evaluate all your options and follow your heart. Hope this helps.
My background: BA in English from a 2nd tier school in China...three years working experience in Chinese government... A Master degree in policy... One year research experience at Harvard Business School.
My problem is my age. Five years are really a long period of time.
Daxia: Congratulation! I am on the waiting list of Wharton (PhD mamagement), but chance is rare.