I'd imagine that Lawson will be playing knuckles down a fair number of snaps. And it's not unusual for a hefty LB to be on the field in a 3 -4. PGH's James Harrison did that for years to good effect.
I'm not comfortable having someone on the field as a "pure" pass rusher. They can become the fall guy on screens and draws, end-arounds, pitch-outs. I'm personally partial to cornerback and safety blitzes.
With the rules favoring the pass attack, defenses have tried to increase interior pressure to hurry the qb into quick pass decisions - which aid coverage.