On the voltage conversion issue, I notice that you have a lot of iDevices. No Apple product I've owned has required a voltage converter. The first one I took overseas was one of the first PowerBooks, to the UK, in 1995. I wasn't sure, so I called Apple Support and asked.
I've since learned about "reading the fine print on the plug," as others recommended. You can also find this info in the specs, or you can check at an Apple Store.
So far, though, I've done OK with just an adapter with three iPods, an iPhone, an iPad, and at least two different laptops over the past twenty years. Travel outside the U.S. has included the UK, most of Western Europe, and Japan.
I don't know why they made this decision, but it seems at some point they decided to make one power supply that works worldwide. Whatever their reasoning, it's beneficial for us as consumers.