The healing doesn't make a huge difference since she has to charge her healing moves to full in order to get measly 1-2% back from them. Most characters won't give WFT that kind of time. I think the main thing keeping WFT from being very good is her kill potential, lack of disjoints, and poor grab/grab followups. She doesn't really have kill setups to my knowledge, her hitboxes are small and she extends her hurtbox out with every single one, and her grab range is absolutely tiny. Meanwhile, she has no guaranteed throw followups past 50% to my knowledge. I'm not too learned on WFT's throw followups though. Her projectile game is actually quite good though it still gets shut down by faster characters. She doesn't have great MU's with most of the cast which is what keeps her from being high on a lot of tier lists right now.
Personally, I think some more mobility would be really helpful for her since her aerial game is kinda weird and she doesn't really move on the ground (short dash grab, short dash attack, etc.). Just my two cents. I've only faced one good WFT in my life so...