Seldom are suites discounted. Very seldom.
You also need to keep in mind that a 1BR suite will only sleep four people usualy...sometimes six. A 2BR suite will usually sleep eight, maybe ten. Just because they are larger doesn't mean the capacity increases. And yes, almost certainly a two BR suite will cost more than three rooms at the CBR, especially if you got those at a discount. Generally a suite will cost at least $750 per night, off-peak.
The one thing you might want to do, depending on how many are in your party, is look at renting DVC points and staying in a 2BR DVC villa (sleeps 8 plus two infants in cribs), which is the same idea as having a suite. Keep in mind you don't get daily housekeeping, but I gladly trade that for the washer/dryer and kitchen, plus the extra room. Depending on the season and how much you are paying for your rooms, that can work out to be a pretty even price...especially if you eat breakfast in your villa.
Anne