Dinner buffet, along with a sit down restaurant that is nicer than the MDR's but not as upscale as Palo/Remy. If you don't feel like doing the MDR, your options are room service or a burger by the pool. I think you need more options than that.
More variety in sailings. I feel like a lot of the ships just do the same ole stuff over and over. I'm sure there is a business reason behind this but it would be nice to shake things up.
An alcohol package. I know some will stick their nose up at this, but it makes everything feel more all inclusive. It probably won't be (and shouldn't on Disney) be bottomless like it is on RCL and NCL, but I don't see the harm in bringing it on
DCL. That alone isn't going to turn a 4 night Disney Dream cruise into a booze cruise. Plus, I'm sure people sneak it on at put it in their Yeti cups anyway.