put vinyl or lino tile directly over ceramic tile EVEN if the grout has been floated. Ceramic tile is concave or convex, depending on how you look at it and levelor will never get a ceramic floor perfectly level so when the vinyl settles it won't retain the memory of the under ceramic curves.
My opinion.
Other options are numerous: remove ceramic tile and re do, lay down cementious boards and build a new floor over this, which would be sooo high and not really feasible, or to lay down a nice low shag carpeting.