I personally spend a lot of time on Ana, she's in my Main hero pool. I love her kit, her nade can really punish enemies really heavily and same with her sleep dart.
I feel like at the same time as she lacks escape abilities her kit compensates for that, if a genji is on you then if you can land a shot and a nade and you call him out to your team then he's usually the one getting punished. Due to her long range healing ability she can stay out of range for snipers, handle most situations really well.