Hey,
Regarding your question of whether or not having a MA/MS degree is advantageous, it really depends on the program! I know some programs view applicants with existing graduate degrees (in the same field) as a sign of commitment and ability to succeed. Others, however, may view it as a burden in that they may want students with a "fresh" blueprint (e.g. no pre-existing graduate school framework). Although I am not in your specific field of study, out of all the schools I applied to this cycle - it was pretty much a 50/50 split in terms of whether or not the committee viewed a MA/MS degree as a positive attribute. You will need to reach out to programs on an individual basis - most faculty members will answer in a relatively honest manner.
In terms of what may have held you back this cycle, it seems like your 58th percentile quant score may very well be it. Although not a terrible score per say, considering how competitive graduate programs in psychology have become over the past years, you should probably aim for at least an 80th percentile score. I know taking the GRE is awful, but it may be worthwhile for you to retake it with added emphasis on the quant section.