The problem with bare styrene is that it is translucent, not completely opaque, and you see a bit into the surface- not much- but enough to spoil the appearance of a painted surface. Sometimes a coat of clear dullcoat will reduce this effect, but not entirely. But that is still a stopgap. Painting is best.
Both brush painting and spraying with spray cans do require a bit of practice. If you are not an experienced painter, practice on scrap plastic to hone your skills before tackling the good model.
Brush painting flat paints is easier than brush painting gloss paint. It takes a lot of practice to do a decent job of a gloss surface, but the Falcon is virtually all flat anyways, right? However, you will need to gloss up any surface to be covered with decals. Then, you can apply dullcoat after decaling to get it flat again.