It depends how you define value. The cruise might not be worth as much per point as in a deluxe resort, however, you might not be able to afford/justify the cruise without the points whereas you can tweak your park vacation.
We've done 3
DCL cruises on points. We have older kids and get 2 cabins. The last one was an 8-night which would have cost us about $5500.00 to pay for! In our opinion that is worth giving up the points. If you do $12 per point my 1 week Aulani stay is about even. If I got $13.00, it's just a few hundred more.
It's all personal choice/opinion.