When we built our new home, I self-assigned projects to construct a darkroom at one end of the basement, and a shop at the other end. I wired the darkroom to have a single switch next to the door that controlled all of the lighting as well as fan that pulls air in from the basement, through a filter, and then exhausts into the darkroom to provide fresh air and create slight positive pressure to control dust migration. There are additional switches next to the enlarging station to control the white light and safelight. That way, when I leave the darkroom and switch off the light, I know that the lights and fan are all switched off.
I thought about doing something like that in the shop, but the difference was that the machines I anticipated having in the shop were considerably larger than the fairly miniscule loads in the darkroom, and the load would be greater than a standard wall toggle switch could handle. But the concept would make a lot of sense in a shop. To actually do it, however, would require that a special switch be used, and that unlike my darkroom, all of the receptacles would also have to feed through that switch. This would call for what is often termed a 'safety switch'. Here's a picture of what they look like. They also aren't cheap - depending on the rating, the price could be hundreds if not thousands of dollars.
I understand how it might make sense to use timers on things like a dust collection system, and they are relatively easy to find (especially this time of year when they are sold for controlling holiday decorations). The one concern I would have is that most of the inexpensive mechanical timers you see in the big-box stores have a cheap plastic gear train, and are designed to have a fairly short life expectancy. Also, check the ratings carefully - I suspect many of these devices are designed to switch the popular LED decorative lighting, and may not be able to switch the heavier loads associated with shop machinery.