Even after two weeks, you shouldn’t be making sweeping changes to your fantasy roster, at least not when it comes to your early-round draft picks.
It hasn’t been a great start for players like Le’Veon Bell and A.J. Green, but overreacting to two games would be ignoring years of massive fantasy production. Barring injury, the foundation players of your roster should be given a longer leash if they aren’t living up to their typical, high expectations.
What you can start looking at are the spots in your starting lineup and bench that were never totally secure to begin with, as you should always be analyzing your roster to find improvements regardless of your record.