This isn't really about the bottom of the pack, but I also think Atlanta and Washington are headed back to the middle.
The Wizards look to me like they're going to slide. Wall is great, and Beal+Porter are nice players, but that team was precarious already with an aging, up-and-down frontcourt. Pierce was good for them last year, whereas his replacement Jared Dudley is an average player. Nene is falling apart and Gortat is a big candidate to regress. If Wall were to get hurt, by the way, the Wizards would fold even harder than the Heat did without Bosh and the Pacers did without George.
... and that brings us to another point, which is that SOMEBODY is going to get hurt, and some East teams are deeper than others. The Knicks look a little better than last year, but if Lopez or Anthony gets hurt, they will be just as bad. The Cavs are a Lebron James injury away from being last year's Miami Heat.