anyone know how big an emphasis Hunter College places on the GMAT?
Don't fret over your score bro. You can do much better than that with the proper strategy in place.
First, call the college and ask them what the average GMAT scores are for students who have been admitted. I think it's better to have a target score to work towards than the ambiguous goal of "just do your best". Of course you want to try your best, but short of perfection having a target score in mind can help you implement a more strategic approach to your prep. The GMAT is just one component of your application. If the average of your school is 600, there's probably no need to spend the extra time working to target a 700. This is even more true if the other components of your application are strong. Furthermore, your target score can help confirm what concepts you should focus on mastering. If your goal is a 600, you're probably better working with OG/Kaplan
guides, whereas if you're targeting a 700+, your prep may include Manhattan's guides. With that said, high GMAT scores can help you in terms of receiving financial aid. Again, just call the school and ask. They may not list this information on their Web site, but they tend to be very generous when you take the time to call.
The kicker is I got a 510 on the practice test I took.
Was this a GMATprep exam? Try not to rely on (or over-analyze) the scores you receive from test prep exams. They're too skewed to be considered reliable. Use GMATprep for a more accurate indicator of your readiness. If this was the score you received on GMATprep than you're probably facing a test anxiety issue or mismanagement of your time.