Ugh, sorry to hear you are dealing with that. Have they looked at the cells to make sure they aren't cancerous (the atypia part)? I think it is important to work with your doctor on this. It's my understanding that atypical cells WITH hyperplasia doesn't mean you have cancer but that you are at a higher risk for having it. You want to stay on top of that. Are they suggesting ablation? How old are you? As to taking natural hormones or not, it depends on if your hyperplasia is hormone related or not. If it is and you have high level estrogen, sometimes countering with progesterone will help. But you have to know if it's hormonally related. What does your doctor say?
I am sorry you are dealing with this. I don't have any personal experience with that. Is the hyperplasia with atypia based on a biopsy from an in-office hysteroscopy or a D&C? It seems that it would be worth trying progesterone or a progestin to reverse it. What has your doctor told you?
I don't know if you had a D&C or not but that gives a more accurate view / biopsy of the entire endometrium and is also a treatment in that it removes those abnormal cells. A three month course of a strong progesterone may also be effective. Hysterectomy is unnecessary 90+% of the time as discussed in this article - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3804006/.
Have you considered getting a second opinion, both on the biopsy (from a pathologist) and your treatment options (from an ob/gyn or gyn oncologist)? I had an unnecessary hysterectomy 13 years ago and wish I had known just a smidgen of what I have since learned about its gross overuse as well as the many after effects. I wish I had not allowed my gynecologist of 20 years to rush me into surgery.