. Why do you think you should get his retirement? He worked for it, it is his. Keep it simple, because in the long run, you could get burned.
No no no no. why would she get burned? she deserves part of it because he was able to sock away at the max (and get matched, probably)-while racking up joint debt--while she reduced hours and pay and ability to save for retirement to stay home and raise kids and run the household. This is how she gets screwed. Maybe he's been planning for divorce--he's managed to contribute to his retirement to the max, but has racked up mutual debt that he's now willing to take on in exchange for the house? NO NO NO. OP, is ALL the debt accounted for? Are you sure he's not been socking away money? You may think it is impossible that he'd do that, but anything is possible.
OP, you need a lawyer and financial disclosure.
as for child support--the courts may determine that but a good lawyer will negotiate a lot for you. You can't afford NOT to have a lawyer. If you want to get an idea of what you might get, there are child support calculators online for some states (including DC).