You've brought up a good point. Chief Freeman in his testimony said that he trusted the system and judges' discretion, but what the public perceives as a lack of consistency is the problem, and the public needs to be reassured. That was one part of his testimony. What you said falls into that.
To me it gets things backwards. If we understand judges are engaging in a balanced and nuanced decision-making process that often requires something less than what a mandatory minimum would suggest, and if the public doesn't quite understand that there are different sentences isn't in and of itself inconsistency...to start from public perception as the basis for public policy strikes me as deeply problematic.
Would you agree that's more or less what you've been arguing too?