what I didn't see on your list was to consult an attorney.
Do that before you move out.
It may be that HE is court ordered to move out!
And to make support payments.
If you want the legal custody of your kids, want to keep them in the same school so as not to disrupt their lives...
all these things count
FWIW...in a study done on divorced women most say they wished they had done it sooner.