I also left a man like this and do not regret it.
What I do regret is agonising over it for so long and not doing it sooner.
Your point one. You can only get on with it for so long before you realise it is actually beginning to destroy you. (I am still working my way through the personal damage and baggage my exh left me with. One day at a time because right now I cant see I will ever fully heal).
Your point 2
It is a worry what other people think. But at the end of the day its not their business and you will find out who your real friends are.
Your point 3. Yes, another worry. Make sure you have a solicitor to negotiate for you. Plus whatever they quote in fees double it. I had to scrimp and save like never before (and have never been well off), for the two years it took to get divorced. Afterwards you get on with it, you manage.
Your point four yes I was worried about that. Teens now see right through him. And are beginning to not want to spend much time with him. Always refused to stay over at his. Sometimes he threatens all sorts with this but never carries it through.
Also when you are not living together anymore. A great weight lifts and you dont feel you are getting anxious when you know he will be home soon etc.
The biggest surprise I had was that the abuse doesnt stop when the divorced has finalised. Although I am more distanced from it, he gets to me and uses the kids as weapons to control me, because he knows I will do anything for my kids best interests.
I had no idea this would happen but it has and does. And each time I realise I have let him control me again I get really cross and frustrated with myself.
My advice is to make sure you get a formal contact agreement in place which should help minimise this problem and which I wish I had.