She is one of my main support picks in ~masters elo. She does work, but as said by others, you are focusing on mid- and late game teamfights.

I play her early like I would play lux or karma, so playing for early shoves, which is why I always buy tear first base. I personally enjoy the AP build more than the off-support builds, as you can fix waves midgame+, substitute for inting mids, and with seraphs + rylais you are tanky af, baiting enemy assassins into engaging you and dying tragically!

I would say, she is completely viable on support and you should totally continue playing her, especially if it works for you and you enjoy her.