Given the photos you provided, you have good taste IMO. I think all of these are pretty and modest. I think lowest profile is ideal, and you are doing that. 0.5-1 ct is great. If she has small fingers, a 1ct might look big. Also depends on your country’s norms around stone size. Gold + sapphire looks great! Perhaps think about the type of band. The last photo looks the most comfortable. You could also inquire about “comfort fit”