First time cruising. Ever

I would want to duplicate a "Four Seasons hotel" type experience on board, to the extent possible, but need to have the ship family friendly as well for a 3 and 9 year old. Port has to be Florida or New York/New Jersey. About 7 nights or so. Any month. I have been researching, but am spinning around in circles. I am thinking maybe Crystal? But I don't like formal dining with kids, and don't want to have to get dressed up, don't want it too stuffy, don't want to be told who to sit with, and don't want to have the passengers join an impromptu hymn choir. Don't want Disney. Any suggestions or am I dreaming?