Sure. For a first cruise it may be a good compromise between a week of WDW and an opportunity to "get your feet wet" on DCL.
I'm a huge Disney fan. When I retired, I actually moved to FL to be close to Disney. I now live about 2 miles from the castle. I've also sailed on DCL 18 times so far. So, I think I've got a good perspective on both WDW and DCL. I'm realistic enough to see that some folks don't care for cruising or base their preference on a different line. So, when somebody asks about a specific cruise Iine I suggest the shorter cruise just so they can give it a fair trial.