I'm not aware of any character issues with Faulk. In fact maybe it was just the opposite. However, he did have contact issues and intended to hold out. I think he also missed some preseason practices, etc. I believe that the Colt's leadership wanted to take the team in a new direction and they didn't want the Faulk hold out to be a distraction or a point of contention within the team. So they dumped him cheap.
In hindsight it looks like the Colts made a bad deal.
I think your post, sums up my feelings completely. Peters has character issues. They are real and are usually detrimental to the team. However, people do change. Bad people go good, and good people go (Breaking) bad.
Based on last season's results, I have to give the benefit of the doubt to our team's leadership. They've earned it.