V.,
Unfortunately, no matter what kind of visiation order is in place you can't dictate what happens in her house. Her house is her house and as long as she is not putting them in any physical danger or abusing them, then there's nothing you can do. I know this from experience.
It's good that you care SO much, but you have to take a step back and look at what is best for the ENTIRE family as far as moving and visitation.
Do your husbands kids need the structure and support your side of their family provides them? I'm sure it is probably the best thing that they have at least one side that is based on a structure and rules. Since these are your husbands kids, what does he want to do? How does he feel about their living situation? These are things you really need to think about before you go back to court. Do you have an attorney to represent and speak for your side?
I've been to court now a few times, and it's so hard to wade through all the choices and paperwork, so I'd recommend getting legal advice of some kind before. My best money spent was getting a lawyer to help me with the language and what things were...it's so frustrating to figure out on your own.
As far as moving, I think you and your husband should sit down and think about a game plan. How will this affect everyone? What are the long term gains and losses? I think you are trying to do what's best for your family, but just make sure that in the long run your husband has no regrets about choices either way.
Good Luck!