As far as Engler all I can say is "Headlee Amendment".
If he did nothing else, fixing the criminally screwed up property tax situation alone made him a hero for all time. Many of the young folks probably don't remember average ($60K) homes with $400 - $600 / month property taxes.
This was yet another vestige of the Blanchard years - like the insane no-fault insurance (with the unprecedented, in-no-other-state "Catastrophic Claims Fund" scam to protect insurance company inflated profits).
He also had the cajones to stand up to Detroit, and cut off some of the gravy train that was all-but untouchable under a democratic administraion.
Now, granted, in the later years, saddled with a non-responsive & partisan state house he became fairly ineffective. And I did not at all agree with the "robbing Peter to pay Paul" approach to neglecting highway upkeep and improvements.
So, despite being a conservative, I can see both good and bad in a republican politician. I must be a "free thinker" too...