It would be a major surprise if Vic Beasley did not lead the 2016 Atlanta Falcons in sacks, to put it mildly. He's talented, he should have a better supporting cast around him, and he should simply be better in his second NFL season, and I fully expect him to clock in with 8-10 sacks and lead the team pretty handily.
The more interesting question is who will be behind him. The Falcons of recent years have been woeful at bringing down the quarterback in any context, but their sack totals have been truly abysmal in 2014 and 2015, in particular, and it would be nice if the player with the second-most sacks on the team had more than, say, three.
My pick is Derrick Shelby with 5-6 sacks. Maybe that sounds ridiculously optimistic to you, but Shelby shouldn't come off the field all that often as a defensive end on early downs and a defensive tackle in nickel sets, and he's certainly got enough talent and nastiness to make an impact. If the Falcons actually get that kind of production out of Beasley and Shelby, I'm guessing we'll be a lot happier with the pass rush this year, even if this team still has a long way to go.