I sometimes just make the whole form wider, then extend the widths of certain input elements as well. For instance, you can make the form wider by adding...
$(".ms-formbody").css("width", "900px");
Then, if you have multi-line input fields (for instance), you can make them wider to fit the expanded form width...
$("textarea").css("width", "850px");
I'm wondering if doing something like that might prevent the wrapping issue you're experiencing with the labels?