I think you have a good profile. You're still young, but it seems like you've already got a few things under your belt, botn in and outside of work experience. Your marks are extremely good, which is awesome because of your over-populated ethnicity for b-school admissions. You also got a great list going already (from stretch to good spots: Stanford --> Cornell). It really seems to me that you've done a good research already on the schools and know what you're talking about. Again, you're still young; apply and if you don't get in, you always have next few years.
To answer your questions:
1. I think you've chosen your schools well. Obviously, Stanford isn't going to admit everyone and even if you have the best of best grades, you'd still need some luck in your application. But it's not unachievable. Stanford's average age is skewing towards a younger population and as long as you have something to offer and make yourself stand out, there's a chance.
2. On the ontrary to Stanford, everyone else is still leaning more towards an older generation (age 25-28). With that said, you'd be competing a spot against a 4 or 5 years of WE guy from some corporate firms. So your weakest spot is really your younger age but if you can convince the ADComs "Why now", you'll be fine.
3. Don't know enough about admission consultants to answer this question justly.