its easy to file defamation after case get over, nothing much to prove, but file along with other criminal charges which make your case stronger and easier.
its difficult to get custody, so file visitation, once child is OK with you, you can go ahead as per situation. but dont forget to file visitation immedietly.
Lawyer personal matter has nothing to do with your case, dont link both, you have any other differences then you can notify BAR council.
You can riase objection anytime, if you have valid points to counter.