A 2" drop is reasonable and if everything feels solid (no excess body roll), you're likely OK as is. I get about the same drop on mine but oncoming traffic seemed to have problems with my headlights so I added air bags to make 'em happier. After I added them, i realized improvement in body roll.
2014 Eagle Premier 331RETS
2016 Silverado 3500 DuraMax/Allison
1975 Corvette & a couple ATV's