One thing I will say is that 10-15 for Chauvin is probably more "punishing" than a normal person recieving this sentence as he has to spend it all in solitary in all likelyhood.
The problem is that he hits so many of the aggravating factors. Anything near the sentencing guidelines would be an insult to justice. He doesn't have any mitigating factors. He showed no remorse or sympathy to the victim or his family. I'm realistic. I don't expect anything close to the 40-year maximum, despite what I personally think he deserves. The considerable list of aggravating factors were already mentioned above.
The thing is that he could've gotten off on a far lesser charge if he'd showed remorse or sympathy after the fact. It could've potentially taken the 2nd degree murder charge off the table. Every image I saw had him looking smug, arrogant, and defiant.