Not so much preventive repair as checking and preparing for the next client, unless there's a fault they're unlikely to do any repairing. If you're hiring a camera you don't want faults on an expensive shoot. The good rental companies also check and prepare their video cameras every time as well.

As has been mentioned, the S16 cameras can go for a year or even longer before being serviced depending on the amount of use it's getting. Although, film cameras being used nearly everyday can get serviced every 6 months. The Panaflex needs to be lubricated more often than other cameras, but it's not a huge operation.

The camera gear can be one of the cheaper budget items, so film production will never be cheap as drawing. Unfortunately, as John Boorman's book title suggests it more about turning money into light.

I think the rolling shutter issue could be mitigated by offering cropped sensor modes, which would also reduce downsizing artifacts as well as offer greater effective magnification. We would see a 1920x1080 or 1280x720 portion of the sensor shown in the rear live view. I can see how this is a problem in a real viewfinder, but that issue doesn't exist on LCD viewing.

yeh but you'd also loose the dof properties which is the whole reason for the exercise