I think a lot of people would look good as Louise, it's more of a matter of whether they can act and hold a candle to Barbra Streisand on camera, particularly in the last scene. Jennifer Lawrence is definitely someone who came to mind, though I wonder if they are gonna go for someone older as Louise to match Barbra's older-skewing Rose.
"Some people can thrive and bloom living life in a living room, that's perfect for some people of one hundred and five. But I at least gotta try, when I think of all the sights that I gotta see, all the places I gotta play, all the things that I gotta be at"