IMHO a career instructor has to be a teacher first and a pilot second.
It's very rewarding, never a dull moment, and you get to go home each night and have a family life, if that is what you want. But you have to WANT to be a teacher, which is a vocation as well as a job, and not just see it as a temporary thing until something "better" comes along, or you won't enjoy it, and not will your students.
As for the $$, I believe once you get up to the top positions in the schools that train airline cadets it's not bad.
But how much $$ do you need to be satisfied? $$ doesn't make you happy. It's all relative. Some people have very high expectations, others are happy to have "enough" whatever their "enough" is.