I think the earlier advice was pretty accurate, and that you'd be competitive in one of the 10 - 20 ranked schools. My advice is a little different, however, in that if you want to hit one of your stretch schools, I think a focus on your career progression and career focus will be paramount. Your GPA won't help (sorry, just being honest). If you got that GPA from MIT or Caltech doing smthg super quant heavy and difficult (like Math or Engg or Physics), then you'd get a pass. The additional issue with your grades is that it wasn't in a heavy quant/analytical area, and neither is your work experience. You don't have to be an engineer to be admitted, but there should be evidence of a comfort level with numbers. Getting some extra coursework under your belt as a way to prove you can do the work would prbly be a good investment.
To me, even if you get your GMAT up by 30 points or so, it won't make a "material" impact into a top 5 program (e.g., Kellogg). Your score is already within the acceptable range, and it's more your work experience and GPA that are the red flags.
With that said, it's great you're at Groupon. There are probably many great essay ideas you have from there. And as mentioned in the beginning, you're a strong candidate at a 10 - 20 school. IMO, Ross is prbly a stretch, but def worth considering.
Former Kellogg adcom member, offering a new approach to MBA Admissions Consulting.