[CalmLogic]

Congrats on such a great profile. As you know, you should retake the GRE, but that will be easy for you.

I am not as familiar with PhD admissions, especially for top schools. However, I would suggest applying to all top 10 ten universities that you are interested in, e.g. Berkeley, MIT, Stanford, CMU, UIUC, UT Austin, University of Washington, etc.

Assuming you have taken the standard required CS courses in your undergrad, you do not need to take the GRECS.

Generally speaking, taking the GRECS can help boost any profile, depending on how well you score. If you could score above 90+ percentile, you would almost be guaranteed to get into a top 10 CS PhD program with your research experience. You really have nothing to lose by taking the GRECS except the fee if you don't have the scores automatically reported.

Though I obviously can't see your transcript, GA Tech would probably be a very safe option for you as they are less selective (and apparently less respected) than other top 10 schools, so I would probably not apply there unless they are better for your research interests.

If you haven't already, I would suggest also posting your profile at the Edulix forum to get more feedback there.