let me tell you
seperated for a year and a half
have a 6 year old
no law contract or great lawyer can protect assets, unless otherwise stipulated in a seperatly aquired agreement
work it out with your wife
agree to the terms of a seperation agreement, this agreement lays out financial compensention, allamony, child custody, and visitation.
once you agree on these important issues then have a laywer prepare.
after living appart for at least a year, once granted from a judge you can make the seperation agreement the divorce agreement
its better to work it out independently of a laywer.
all being said, any agreement can always be reopened.
good luck