There's a LOT of middle ground between the focus of Dark Sun and the kitchen sink that is the Realms. :p
And what I'm saying doesn't widen the focus at all. It just gives the DM some idea of what nasty Dark Sun dangers might be lurking outside the Tablelands.
I'm not suggesting that right...
Two items, Stone of Good Luck and Cloak of Protection are uncommon items, and the Ring of Protection is rare. The rest are going to be harder to find. Yes, they take attunement, but that a choice the player will have to make. Choices are an important part of the game.
Also, if we drop to...
For a small area, though, it has a lot packed into it. I have the older stuff and there's a lot there. Also, I'd love to see the Tablelands expanded in size or at least some space dedicated to ideas for the DM to use if the players leave and go into the Hinterlands.