What type of hotels do you stay at when you travel by car? If it is the Ritz then category 12 is for you. If it is a Marriott or Hyatt, try the 9 or 11 mini suites. If it is a Sheraton or Holiday Inn go for the oceanviews or interiors.
I myself have been in all categories from interior to suites. I prefer the extra touches you get with a suite but most of my cruises are balcony staterooms. I will not even consider a ship if a balcony stateroom is not available. That in itself is not so bed because I eliminate most of the older ships that do not have balcony staterooms.
For your first cruise two category 6's would be a good start. Ajoining rooms are the best. When you do try a balcony watch out. Ask if the ship you are sailing on offers any family suites. They are very popular. One sitting area with two bedrooms and two bathrooms. Most can sleep six to eight passengers.