Oh. We have a terminology conflict. What you're calling streaks are actually brush marks. Streaks means (to me) that you can still see the old color through the paint. If brush marks don't go away, your paint is too thick. You can thin it a bit (_only_ a bit), or you can add Floetrol (Penetrol for oil paint). Floetrol increases the surface tension, thins the paint, and slows down the drying so the paint lies down flatter, hiding the brush marks.
Well, a thinner paint will help some, but there's no way to completely eliminate the hatbanding without using the same device to apply the entire surface, whether it's a brush, a roller, or a sprayer.