Yes, the Zomei tripod I described in my post, which I've used for over five years, does indeed have a hook on the bottom end of the center column from which you can hang your camera bag to provide more stability.

As for the camera mount, the Zomei ball head is designed to accept the Arca-Swiss Standard mounting system brackets. Note that all of my current cameras (4), as well as my 400mm long telephoto lens, has a Arca-Swiss mounting bracket so they can be quickly attached/removed from the tripod. In fact, I've added a Arca-Swiss receptor on my older, and larger, traditional pan & tilt head tripod so that it's compatible with all of my gear, including BTW, that Busnell Spacemaster spotting scope, as I've added a mounting bracket to it as well. Even the focusing-rail, that's part of my macro kit, is designed to not only mount on a Arca-Swiss compatible/equipped tripod, but it also accepts a camera with a Arca-Swiss mounting bracket. As I've mentioned, I've supplied all of my mountable items, cameras, lens, etc with a single standard quick-release system. It makes life very simple when having to work quickly in the field.

Each year the ability to make better chips improves, and the quality of smaller sensors does too. Moore’s law isn’t perfect, (every 18 months you get twice the capacity for half the cost) but it certainly illustrates the trend.

While you are specifically mentioning formats common to pro and amateur cameras, consider also the trend to even smaller sensor formats which are buried in cell phones. Not only are the tiny sensors very good, but the computers they are attached to get better every year, too.

I think pictures from last year’s 12 mp cell phones are as good as pictures from 12 mp cameras of a decade or more ago. And future year’s cell phones will be even better.

A hundred years Leica showed that with higher resolution film, and higher resolution lens designs, a 35 mm camera could produce images on par with what a 4x5 press camera could produce. In a much smaller and lighter system.

Some of the improvements in small format were picked up with larger format gear and emulsions, but obviously the market shifted to the smaller size. Cell phone cameras are now that smaller size.

You’ll probably see something similar play out over the years with digital. Innovation in tiny sensors for cell phones will be applied to larger sensors used in cameras.

The question you might have asked would have been about even larger sensors. Look at the other end of the spectrum, too: there aren’t a lot of physically big sensors on the market at any cost.

I think Lots of people are waiting for a cheap 4x5 sensor with even 1 mp per square inch—the equivalent of a 20-year-old 1.5 mp full frame camera—but multiplied over 20 times the area. It would be a 20 mp large format sensor. And if they could make the 60 mp chips (about 40 mp per square inch) then there would be something between 1000 to 1200 mp on a 4x5 format!

I think the bigger chips are just too difficult to make currently. I guess they find more flaws as the chip size increases, which makes it more expensive to produce bigger sensors.