I've seen normally upright trees styled as weeping trees, and it can work if you are persistent with wiring. To be a weeping tree, every branch needs to weep even the little ones.
My friend has a bald cypress , a normally upright tree, and once a year every branch gets wired to position, just before the August bonsai show. Looks great for a couple months, then in spring new growth starts pointing straight up. From spring until it's wired out in August, it looks goofy. Then it gets wired out and looks great.
Give wiring a try, see if that helps you create the image you want