I think that's a good idea, though you don't need to feel the need to "check any more boxes," per se. Your clinical hours are definitely, in literally no way, shape, or form, "on the low end" (especially this cycle..) so you don't need to grind 15 hours per week to hit 600—I doubt that would make any difference at all. You didn't mention any shadowing so that's the only thing that is legitimately missing/low on your app. Otherwise, you should pursue things you care about to further stand out.
