“The Dean" does not do “chances." If you would like to pay $150 for a professional College Karma “Stats Evaluation," I think you will find it money well spent. Go to http://www.collegekarma.com/college_counseling/college_counseling.htmand look for “Stats Eval" near the top of the page. The evaluation will give you your “chances" at Harvard and at any other college you name on the Stats form. It will also give you suggestions on how to improve those chances, when possible, and will provide recommendations of other colleges that meet your profile and preferences.
Although it is irresponsible for this “Dean" to offer you admission odds without a lot more information, what I CAN tell you is that that Harvard is swamped with Asian applicants who have top test scores and very strong music accomplishments on their applications. Many speak Mandarin and other languages fluently as well. So you haven't shown me anything that will distinguish you in this hyper-competitive crowd. You also haven't told me if you have just one or two B's on your record or many. Although Harvard does admit only outstanding students, there is some wiggle-room for less-than-perfect grades … especially when other achievements overshadow them. However, from what you've said, your accomplishments are impressive but hardly unique.
BUT … as I said before, I have too little to go on here. You can consider a Stats Evaluation to get another professional opinion that is based on more information, or you can give Harvard your best shot and see what happens. I've been in this business for three decades and, each year, there are always admission decisions that surprise me.