Doubt GW or D3 need a R9 290...
Dota 2/ LoL* also don't need that horsepower
Any last gen card thats cheap can tackle these titles easily, like GTX670~680,
they are not that expensive anymore.
Her usage is gaming and photo editing.
If she is not overclocking, will i5 sufficient?
in normal user, i5 is more than sufficient to tackle her needs.
Unless she got plenty of money to dispense or ridiculous Image Rendering work to do, i5 will still be enough,
just that its slower. So I assuming her photo editing is clear pimples and wrinkles, i5 is more than enough.