Why do you assume that Schwartz is going to use the same schemes against the Dolphins as he did against the Bears? He has an excellent record as a DC, so this isn't his first rodeo. Tannehill to Mike Wallace or Brian Hartline is NOT nearly as potentially dangerous as Cutler to Marshall or Jeffery. Miami is much more like the Bills than either team is like Chicago. Different teams, different game plans.
I think I'm one of the few Bills fans who did NOT bemoan the loss of Mike Pettine. Last year, Pettine's attacking, gambling style worked well for the DL personally (3 of 4 went to the Pro Bowl), NOT so well for the Bills LBs (and the run defense) and the team's win-loss record, so I'm more than willing to give Schwartz the benefit of the doubt.
The Bills have added two LBs to help against the run: Manny Lawson and Brandon Spikes. Unfortunately, they won't have last year's outstanding rookie LB, Kiko Alonso, who is on IR, but they'll get Nigel Bradham, who's taking his place, back from a 1 game suspension. They seem significantly improved against the run.