Before you guys opine, just know that I can't get that high again, as my highest practice test score was 660.
Well, the fact that you got 700 on an actual test, while not being able to score more than 660 on practice tests, should be telling you that practice tests are not a perfect predictor and also that not prep providers, however smart and dedicated, have not been able to replicate the GMAC scoring/"question picking" algo perfectly (which is perfectly normal).
Knowing your own practice tests scores, would you have believed if someone had told you in the morning of the actual 700 test day that you will achieve a 700 score? Probably not.
I believe you should try again, especially if the time spent on the GMAT is not going to hurt the other parts of your application (because I also do believe that it is perfectly possible to be admitted to a US top 15 programme with this score, provided you prepare the rest of the application well).
A better Q score will probably be quite essential in view of the "low GPA w/ varying grades across analytical subjects". Focus on it, hunt specifically for 700+ questions.
This being your first post on GMATClub tells me that you probably still have ahead of you the great prep opportunities that this forum provides - explore them - you will later appreciate how much it has given to you!
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