At my last company, I stayed at an unfulfilling, dead-end job for years because of similar reasons to what you listed; kids were settled, I was comfortable, and not many opportunities to move up in the company. I moved to a new company 7 years ago and the switch has been very good for my job satisfaction and mental health, and I've had some chances to move to a couple of different manager roles, so overall it has been a huge positive.
On the other hand, switching locations right now might not have the lifestyle improvements you are hoping for if you end up being house-poor somewhere else, and deciding whether or not to uproot the kiddos is always an important consideration.
So I don't have any suggestions for you, but be prayerful and best of luck to you and your family.