Thank you all for the input, the summary of which appears to be "You need to focus on your application holistically and, to that end, seek out professional advice from an admissions consultant." I will do some research on this and make my decision accordingly.
As for the GMAT,
EMPOWERgmatRichC, you asked why I'm waiting until August to take the test. Well, I suppose I see some distinction between a score in the low 700's and a score in the high 700's. I
do understand that this score is a small part of a larger package, and is perhaps more of a "you need to score well enough" (i.e. a boolean trigger) rather than an input item with a positive slope. But I can't yet let go of the hope that with some effort I can reduce the risk of scoring below a 760 and increase my odds for an even better score. Given that my first score, without much study or exposure, was 710, and only after a week of additional studying was I scoring in the 750-760 range, it seems like a worthwhile endeavor. (Can you say definitively that it wouldn't make much difference?)
Also, thinking ahead a bit about what my narrative will be in my application essays, if I were to be truthful (which I always aspire to be), it would probably focus on a love of lifelong learning (one of the reasons I initially chose to become an actuary), my theoretical and thoughtful nature, and my ability to approach issues and problems holistically and uniquely...or something along those lines. I haven't really fleshed out anything specific yet, but I feel that a lower score might limit the types of things I can discuss in my essays without sounding a bit over-the-top.