J.W.
I could tell you what I missed, or how I should have prepared but like anything you can't be prepared. It is just the nature of divorce.
One thing I did right is I didn't demand unreasonable things. One of the things that floors me reading some questions is there are women that expect their life to stay the same sans husband. That just isn't reasonable and if you fixate and fight for that you will get less than if you were reasonable.
My ex is not poor and I could have got spousal support until my youngest, who was five, graduated college. It would have been an amount that I could live on but not the life we were used to. So I was reasonable, I asked for spousal support enough to sustain the lifestyle I was already living in return for capping it at four years, just enough to earn my degree, and I did.
I still lead the lifestyle I did before my divorce, well I am not a stay at home anymore, but that is the the thing, you have to have skin in the game. If you are unwilling to negotiate things will turn out badly. About the only people who will win are the attorneys.