Realistically, out of 170+ books a lot were pot-boilers - but there are at least 20 absolute gems in Andre's work and that's a good tally for any writer, even without 150 other books on top! She was the second SF author I remember reading, after Jim Blish, and I was mad on her works throughout my teens and early 20s. I never really cared for the Witch World books (except Year of the Unicorn) but I loved the early pure SF - Star Rangers is still one of my favourite books. I re-read it recently on-line and it was just as good as I remembered. And Fur Magic, which is marvellously creepy, probably had a formative influence on my becoming a pagan.
She was also a thoroughly nice person and a game old girl who was still doing high-kicks even in a wheelchair! Although we will all miss her, I should think she's very glad to get shot of her failing body and be able to be active again.