I hate to be the nerd that goes "akshually" but even if we wanted it to be a sequel to the 1990 movie, the Roninverse and 1990 continuity don't line up.
As an example of one nitpick: in the Roninverse, the drama with Tang Shen involved Saki's father, Nagi (yeah, he's his dad in that continuity). And Saki's death was completely different.
The point is that there'd be some continuity-bending to make it work, creating a new and separate movie Ronin-verse continuity. I think for simplicity's sake, as long as the movie is based on the comic, it should be as true to the lore of comic as possible. It take some creative liberties with how it portrays the events of the comic, but at least the lore/backstory should remain in-continuity.
Also, I love the 1990 movie as much as the next guy (probably more than the next guy), but I think it's time to move on. People have this weird cult around the 1990 actors, but I think we don't need to bring back Corey Feldman or a balding Elias Koteas. And while Judith Hoag does look good at 61, I don't think she'd cut it for the flashback scenes — they'd need to go with a younger actress and just use makeup for the older April scenes.
