He should ask for joint legal custody. That means that he would have as much rights as mommy to make decisions for his child. THIS IS IMPORTANT because without it, he won't even be able to get copies of his child's report cards or medical records.
He should ask for as much time as he can for visitation. I personally would ask for full custody, then settle for joint physical custody, with visitation occurring as follows:
He gets the child Tues, Wed, Thur and every other weekend. Alternate holidays (he gets Thanksgiving, she gets Christmas, etc. then switch the next year.)
He should also ask for the right to claim the child as his dependent on his tax return, ESPECIALLY if he ends up having to pay child support, because child support is not tax deductible to the payor and not claimable as income to the payee.
He should also ask that medical expenses, including insurance costs, be split 50/50 with mommy.
NOTE to hexeliebe: Not sure which states you're talking about, but in the past two years, I've seen this issue come up in California, Utah, and Ohio. Without legal custody (not physical custody), the non-custodial parent cannot even check the kid out of school early! The schools require court papers that show the right to obtain information or custody of the child.
I have attached a search to targetlaw for San Antonio Custody Lawyer. I would look at a few websites and make a decision based upon your specific need. good luck