But there are generally ranges someone can be convicted in, for certain crimes 1 to 5 years, 5 to 10, etc.
That he got an 800% increase in sentence doesn't matter, as long as the conviction fell within the ranges set up by the law.
You can call a judge biased, but if he feels it's a correct sentence, then you're out of luck. You do know that is why we have judges right? In part to make judgement calls on sentences.
That's not how sentencing works. Unless the judge is up against a mandatory minimum, s/he has ranges to work within. Intent and attitude (lack of remorse, etc.) absolutely factor into that sentence.
Dumbfounded by your words, a 800% increase from the average sentence is, I think completely ok in a just system.