Would prefer either darker or lighter trousers. Perhaps I'm not a fan of that kind of jeans, but I think either unwashed denim or more faded or cream linen pents would do better.
The formality dissonance doesn't work for me either. Tie is too formal, as is shirt. I think a white or white linen shirt, or a blue oxford would be good, but lavender (and other pastels) are almost entirely business in a dress shirt context (polos being different but I hate polos), speaking of I imagine button down would also bring it down a notch. A knit, wool, or rough silk tie would okay, I think.
But I do like the jacket.