MD/PhD?
Thats a beast level of research production.
No PhD but did take a year off to do research. I knew I was someone who wasn't good at standardized tests even before taking step 1, so started research early (fortunately got interested in radiology early on). I had a good amount of "low hanging fruit" projects, which I got pretty good at identifying after doing a couple that weren't haha. Also had a couple of high-risk, high-reward projects that fortunately panned out well.
As for the MS3 asking for advice, I just presented myself (personal statement) as being highly interested in research, focusing on some of my specific research interests and how I want to help advance the field of radiology. I think being able to formulate specific interests, even if they may change, is important. I imagine PD's hear a lot of "I'm interested in research" but that doesn't really mean much. Note, by doing this I believe it hurts you from getting interviews at some not as research oriented programs. I was actually rejected by two of the above programs, but appealed them by emailing the PDs with specific reasons of why I was still interested (used the AMSER guide template). During those interview days the PDs apologized and said they assumed I wasn't actually interested in their program.
I also think I had very strong letters of recommendations from some big names, which was likely a factor. No programs I interviewed at mentioned my step 1 score (230) as a concern, although its probably why I didn't receive interviews from MGH or Michigan which I'm okay with. One other thing you can do is become a reviewer of a journal or two. Radiology, AJR, and JVIR will likely let you be a reviewer, which I actually find entertaining and a great learning experience. You just have to find a good mentor who is an established reviewer for said journal, state you're interested in reviewing for them and that you want them to be your mentor, then email the editor saying you're a med student interested and have Dr. Blah as your mentor who will oversee you.
Using SDN users step 1 scores as reference can often be daunting, but its not the only thing and there are many other ways to sell yourself.