While Wright may be perceived as a role player, there are three things he does extremely well that will be missed.
He is willing, able, and determined to block oncoming pass rushers. This is a rare talent in the NFL, especially combined with the second aspect.
Wright has soft hands, and is dependable in catching passes in the flat, which is normally a quarterback's last resort before getting sacked.
Special Teams Play
Wright is fearless, and easily the second best special team defender on the the Browns, obviously to Cribbs. This is not that hard to replace, but again, the combination of the three factors is.
Lets be clear. By no means do I think Wright's a superstar. He is at best average at reading and getting to holes. Wright has below-average speed and power.
Regardless, finding a replacement is not going to be easy, as emphasized by Harrison's inability to learn how to pass block.