You seem off on the pricing, if a set of 7 lenses cost 39000 then it comes out to be 5500 a lens!
I don't know, you would have to check the specs on both the camera and the assist. You may want to reconsider buying something with a screen though, as the screen on the c100 is quite nice, no need to bulk up your rig with another and the big batteries needed for those. That is why i recommended the ninja star, as it is tiny and weighs only about 100 grams.
No worries. Something like an atomos ninja star can be nice for this if you want it, as it is very light and won't add a lot of extra weight. The difference in codecs is the reason I prefer the C300 btw, I believe that has a 50 Mb/s codec which gives you a nice, rich picture (I see the mark ii has many, higher bitrate codecs but the older one has a nice picture too).
The lowest F stop and the shutter greater than 180 degrees are both detrimental to sharpness (if shooting handheld), they are only helpful if he doesn't have the correct exposure. Ideally he should aim for higher F stops for better optical performance and greater depth of field (not too much though because then diffraction kicks in) and keep the shutter at 180.
Wide angle shots usually have more in focus. The more you have in focus, the more information there is in the picture that needs to be stored. The C100 does not have really high bit rate codecs, the 28 Mb/s you have means the picture will be quite compressed out of the camera. This is less of a problem with low DoF images or less busy images because there is less information loss. If you have access to an external recorder, you could try a test recording with that and see if the less compressed image you get is more pleasing to you.
This was the only thing that I could think of re: films and procrastination.
I find that it helps with procrastination when you have set tasks and a boss who kicks your ass if you don't do your work. In general, working with other people helps cut down dead time.