I think the idea is to keep with less rich colors because the jeans are so dense with color, if that makes any sense.
The ideas of white, ecru and even black are good ones. Grey can also work, as could possibly a light blue like a powder blue. Since it's the top it does make more of a difference in terms of what you look like, though. Me, I'm blonde and light so those colors all look good on me except for dark grey. If you've got black hair, dark eyes, you probably do better staying away from ecru and going more towards a purer optic white. And the blue, if you choose it, should be a clear blue, not mixed with any green or red. No green because that wouldn't look good on you, and no red as it would essentially look like just another version of purple on you.
I wonder if a gold or light yellow would be all right. Maybe to amp up the richness with gold (probably just for going out).
Does that make sense to you?