Consider this, no other material came after blade runner other than maybe a book or two or three.
BR is such a huge gamble, you know the marketability of a film like it is very shady at the moment.
I think if BR sequels come out it would be at the forefront of some very major productions that help the genre or a lack of genre movies those of which that will bore the snot out of you.
Prometheus 2 is still mewing about and there is more hype for Giger's monster than there is for ...i don't know a poetic origami unicorn.
The cast of blade runner's sequel will probably spoil those who were fans of the original simply because it was released at a different time then and those stars really had their moment. I don't think they could pull off another lineup like that. It was more haunting than magical really.
my pessimism is needed.