The 3/4 oz load you reference is a good one. No complaints here.
They run about $7.00/bx all in. So when I can get Federal 100 packs for $32.50, my press sits, and I accumulate Federal hulls.
Green dot isn't super punchy, and a lighter load softens it even more.
5/8 oz in the 20 is a little more fiddlesome.
I think you can probably get her a long way shooting the 3/4 @ 1150fps.
Every new shooter experiences fatigue at first. Work with her on it. Rest, stay hydrated, use a tote for cartridges.

Out there doing it best I can.