I’d advise experimenting with her a bit longer to test against the current meta.
Potentially, she is better than even Gravemaker, as she deals more direct damage, and her heal steal could be higher than GM’s DoT and personally, I consider heal steal just another form of damage.
However, most teams I face nowadays either use Telluria/Heimdall tanks as the sole healer or don’t use a healer at all, which means one of her top features becomes useless, as the tank usually goes down before she fires. She’s still a very useful hero but is it worth it to you only for her low damage and short protection?
On a related note, I"m very intrigued by her idea as a tank and I’d love to hear more from people that have used her in such a way.