While your advice at the end is good, what precedes it comes across as "I am perfect and always right, and these guys were a bunch of dishonest incompetents."

While your advice at the end is good, what precedes it comes across as "I am perfect and always right, and these guys were a bunch of dishonest incompetents." I have a hard time believing that view. At the very least, you did not do a good job of evaluating your future employer, and once in there, you did not do a good job of influencing them to follow your lead (without pissing them off).