I think Disney picks different organizations every year. I believe last year or the year before they donated to the local United Way.
Make-A-Wish is still really good. "Fun" fact about MAW - each chapter kind of operates as their own organization. So MAW Southern Florida operates separately from MAW Central & Northern Florida. As such, each chapter has varying levels of money that goes directly back to the wishes vs overhead and marketing. For example, I just pulled the financials for a few chapters. Southern FL says 75.4% of their money goes back to wish granting while Central and Northern FL says 74% does, the Greater Los Angeles chapter does 71%, the Mississippi chapter does 71%, and the New Jersey chapter does 78%. WDW would probably donate to Central & Northern FL, but if you personally want to donate either find your local chapter or find a chapter that has a good percentage of financials that go directly back to the kids. 75% going back to programs and services is a pretty average for nonprofits as a whole.
There are also a bunch of smaller wish granting organizations out there. There are a few chapters of The Dream Factory around the US, and they say that 96% of their funds go back to wishes. They are also mostly volunteer driven so they don't have full time employees like MAW. It looks like they are similar to MAW but also grant wishes to children with chronic illnesses and disorders, not necessarily children with life-threatening illnesses.
Of note, GKTW has 90% go back to their mission which really is fantastic!