Don't take a lowball offer. That's what I did when dealing with the insurance adjuster about my fence that was run through by an SUV. I thought it would cost more in legal fees to pursue it. I recently found that as long as you win the case, your fees are covered. Had I known that, I would have gone through with a case.
I hope your pregnant wife and baby are OK.
If you haven't already, make sure she gets checked out THOROUGHLY. I believe you can seek damages (healthwise) for at least a year after the accident regardless of a settlement.
Good luck with everything.