I won't go as far as to say they will have a dangerous pass rush. That remains to be seen. However, with the new approach, fresh legs, younger better players than the street injured guys they were forced to play last year. They only can improve.
As to getting more sacks, that's not so much the issue. Just be consisitent. Then the sacks will come later. As a group, yes they can form a decent pass rush. they don't need a sack leader, as in Ware. They need to have guys with multiple sacks, so the QB doesn't know where the pass rush is coming from. They won't know who to double team. Until someone may step up to be that guy.
Stop the run, pressure the QB. Hopefully the secondary will finally show we have some players. Still all remains to be seen. But I'm going into this season feeling better about this defense than I have for a while, even with all the changes and new players. Kind of like when Jimmy was getting his defense together, but he had higher draft picks to work with. Actually I wonder how many high picks were taken on offense vs. defense. That's another thread though.