So, I could really use the advice of the community. I know that this overall is a pretty good score, but I know that I can do better. I think nerves got the best of me on my first take of the GMAT during the Quant section; my last 4 practice tests I scored between 750-780. I'm concerned that the 45 in Quant will be a significant strike against me as it is only 71%. I'm very conformable with math and numbers, having taken though calculus and statistics in high school, I was able to test out of having to take math in college. The 97% in Verbal helps, however I am a bit of an odd case to be apply to business school. My profile is as follows:
Program: MBA(FT)
Area of interest in MBA : Strategy Consulting/Entrepreneurship and Innovation
GMAT: 720 (Q:45, V:44 AWA:6.0)
Undergraduate: small private school in in Los Angeles with a 3.8, double major in Philosophy and Industrial Organizational Psychology with an Emphasis in Leadership and Management. Also graduate of Torrey Honors Institute (rigorous great books program that essentially dd case studies on great books, Socratic/tutorial methodologies)
Work experience(WE): Here is where I feel lacking, 5 years total; 2 years in what has been essentially freelance strategy consulting. I had the opportunity to direct a marketing program for a Hungarian upstart, and have been very successful in each position (I can link to a resume if it would help assess my question). Nevertheless, I simply don't have as much work experience as the average applicant--plus I'm currently unemployed.

Nationality: American
Age: 24
Gender: M
I know what I want to get out of the program and have a specific idea of both short and long term goals after applying. My questions are essentially as follows:
1) Should I retake my GMAT to get up my Quant?
2) Are there other things that I can do in order to demonstrate to business school my analytical and quantitative proficiencies?
3) How much of a shot do I have, or should I wait until I am older and more experienced?
I really want to go to Darden, as I love the case study methodology, I have some friends who are Alumni, and the man who mentored me through undergrad passed away while attending the Darden MBA program. However, I'm shooting for any of the stars - Harvard, Stanford, Wharton, Booth, Kellogg. I am certain that once I get in I will do very well at any of these schools, but getting in is the hurdle when I'm competing with folks who have 11 years of experience. Thoughts community? I appreciate your time to help me out!