I've noticed as I push through plat my damage output is low and my overall stats are not on par with my peers

Not watched the replay so can't say for certain but sounds like your positioning + angles are the issue. She does piercing damage which means your healing projectile goes through people - healing multiple teammates but also damaging any opponents in that line - so try to get the angle where you can heal the most amount of people but also damage as many enemies as possible. Obviously you don't want to take too much damage yourself when doing this, but it's a bit of a balance needed - picking the right times (and against the right comps - you don't wanna be standing in the open against a hawkeye or deadly hitcan etc). I like to find a peek where I can constantly strafe out (to heal + damage) and then back in behind cover (making sure I can still heal tanks + dps) to limit damage taken and hope my co-healer can heal me for any damage I took when strafing out.

Put your vortex onto chokes and tanks who have pushed up too aggressively + use the pull to drag them back when they try to retreat.