I was totally stuck on whether to take the GRE or GMAT for grad school. After freaking out about it for weeks, I finally decided to look at the actual programs I was interested in. Turns out, some programs accepted either test, while others had a clear preference for one over the other. A couple even had hidden notes saying they were test-optional!
So, my advice? Create a spreadsheet of the schools you're considering and make note of their testing requirements. I wish I had done this sooner because it really helped clarify my decision. In the end, I went with the GRE because it lined up better with my strengths.