Saw it today with the wife. Meh...
Yeah, I don't see these happening. Visually impressive, but the first half of the movie plods along, story is pretty weak, and the acting is mediocre. Cara's a cute kid, but she has about as much talent as a tuna-fish sandwich. And that hideously ugly kid that played Valerian had me laughing when he mentioned how handsome he is (yeah, not even in their universe; that putz looks like a heroin addict). I don't foresee any future outings for this duo. I don't know what's happened to Luc Besson, but his movies of late have been fairly sub-par. I miss the days of La Femme Nikita, Fifth Element and The Professional.