Sounds like you talked about the "mommy name" and who is going to get it if you birth a new baby -- YOU.
What about other questions? Did you get a chance to cover those?
How supportive is each person's family right now to polyshipping? Your family of origin? His family of origin? Her family of origin? How supportive is each group to a new baby joining the family?
Have you discussed NOT cohabitating if you choose to move forward with TTC?
Be neighbors if you like... but at the end of the day people can have their own spaces?
Have you discussed how this will break up if things need to break up POST baby?