Hey @Alphyn
It looks like you have great internship experience and your GPA is in range.
Like you mentioned, I think your quant score is the weakest area of your app. Most of the schools on your list pride themselves on their quantitative rigor, so I think you should shoot to at least get over the 155 mark (160 would be best!). With a 149, I think Heinz and Ford might also be a reach right now - Heinz's bottom 25 percentile mark is a 153 - Ford doesn't list theirs, but based on applicant's posted scores this year, I would guess it was a bit higher. I was able to up my quant score using one of self-paced courses that had a large test bank, so I could identify the question types I was struggling with and focus on that type (I jumped 158 on my practice test to 163 during the actual). You seem to have taken a lot of undergrad quant classes, but maybe taking a stats class this summer would help as well. Still, the GRE is only one aspect of your app!
You could also focus on playing up quantitative aspects of your job in your resume and SOP - GSPP, Heinz, and Ford all give you a ton of space in the SOP to really dive into your work experience. Maybe once you complete your VISTA year, you could look for jobs that focus on budgeting and data analysis.
Have you considered pursuing an MPH?
Hope this helps!