You shouldn't buy
DVC to trade out your points to the cruises or the Disney/Concierge collections. It's a poor value for use of the points. It is nice to have the option, but it would be a once every 5-10 years kind of thing...if I ever even do it at all.
If you don't mind a small amount of hassle, you can get a much better value for your point by renting the points out using a service like David's
DVC rental which will generate cash (between $11-13 per point, depending on the resort you buy).
For example, a 7 night voyage on the Fantasy in 2016 for an ocean view stateroom with verandah will cost you 280 points per person, plus a $95 reservation fee. So for two people on a cruise, it will be 560 points.
If you take those same points, and rent them out using David's DVC rental, you will get $6,160 in cash. The same cruise, to book in cash, costs $5,042 right now...not taking advantage of any specials. So, the $6,160 the points are worth, plus the $95 reservation fee, means that the cost difference between using points directly with Disney versus renting them yourself is $1,213. For a little bit of work, you now have $1,213 in extra spending cash on your cruise.
The $1,213 in extra cash is just based on the retail cost of the cruise. You could probably work out a better deal by booking the cruise with a
Disney Travel agent since they can throw in some extras like onboard credit and take advantage of any discounts and specials that Disney is running. Whereas the
point charts for cruises are fixed 2 years in advance and don't come with any specials, discounts, etc.
Now it is a little bit of work to rent the points versus just making a phone call to member services to book the cruise. But probably not more than 2-3 hours.