As one of the people who routinely tells people using points for cruises is not a good use of points, I want to defend that position just a little bit.
First off, obviously you can and should do what makes sense to you with your points. Whether it's the "best" use of points is not really super important. They're your points - enjoy them!
It's primarily a consideration for people thinking of buying
DVC. I just want folks to understand before they buy that using DVC to stay in DVC resorts is a big discount from cash, but the exchanges are not. In other words, buying DVC to mostly use for cruising or other exchanges would be not worth it. You're better off saving your money and paying cash for that stuff. So if you figure you'd like to take a cruise maybe 1 out of every 3 years, and go to WDW for 2 out of 3 years, you're generally better off buying 2/3 as many points, using them only for DVC, and using cash to take cruises. If that sounds like a massive hassle, then that's not workable, but it should still be pointed out.
For folks who already have points, and want to use them for something other than DVC resorts, using them for cruises and other hotels is a nice convenience and certainly much better than letting them expire. As people have acknowledged in this thread, it's almost always better financially to rent out the points (directly or via a broker like David's) and use the cash to book the exchange. You almost always have enough cash to cover the trip and have money left over for postcards and t-shirts.
But there's no question that even if you use a broker, renting is somewhat more hassle than just calling up member services and booking the exchange. That said, I think folks who are wary of renting might be very surprised at how little work is involved if you use David's. I was kind of surprised myself. It's impressively easy. You still have to make the booking, but they do all the customer service and hand-holding. And while there are risks to renting, David's has a reputation to maintain and I think it's likely that they would make things right if a renter did something bad. At minimum, I think using a broker would tend to scare away the more flaky and/or scammy people. (Is "scammy" a word? I'm going to say yes.)
But no one should feel that it's "wrong" to use your points the way you want to use them. That's for sure. It's all just tradeoffs and choices.