I'm glad to see Riddick back. I always felt that Chronicles was pilloried a bit unfairly. The movie wasn't perfect but I thought it was a good space opera film. I liked the Necromongers a lot and Dame Vaako was one sexy space Lady MacBeth.
As for the new film it seems like Twohy and Diesel have distilled everything down to what they think the fans want, more monsters and more bounty hunters. Hopefully they will get better results this time than with Chronicles. I'm pleased to see Katee Sackhoff in this. Though I'm not so sure about the monsters this time. I really liked the ones from Pitch Black.
Looking forward to check this out when it opens.
The story is also dictated by the budget. They had a big budget for the sequel, and a smaller, more Pitch Black budget for this new one.