So just to compare my choice with yours this is what I would by:
Sony Alpha 6300 - 1.000€
Sigma MC11 EF to E mount adaptor - 250€
Sigma 18-35mm f/1.8 EF - 800€
Sigma 50-100mm f/1.8 EF - 1.000€
Tascam DR-60D Mk II - 200€
Rode NTG2 + Boombole + misc. - 400€
MacBook Pro 13" - 1.500€
Manfrotto 502HD Tripod - 300€
The answer is very simple but most people explain it much more difficult.
You have to over expose your shot about 1 1/3 to 1 2/3 stops as you would normaly do.
It's good to use zebra at 70% to check your subjects skin tones. They should be around this value if you shoot SLog3. The reason for the noise is that you underexpose. SLog3 loves light so give it light. Shouldn't be a problem with the A7S II.
This also the reason why the native ISO for SLog3 is 1600. If you over expose this way it's more like ISO 400-500 and that's very agreeable with NDs.
It's all right if your image looks a bit blown out in camera but if you grade it the brightnes will come back to normal because most CC/grading is making the image darker than it was before.
That was Michael Tiemann says...
And also - completely independent from every other aspect - it depents on your shooting style. Do you shoot at longer ort short focal lengths? The kit lens doesn't offer a proper tele look.
Primes have a better image quality because they are one focal length at all times and the image quality is focused on that on length. It's a good way using a prime (like a 35, 50 or 85mm) to know how different focal lengths work and also to use your feet as a zoom instead of focal lenghts as a zoom because focal lenghts are not ment to be used as zoom (at least in film) but to deliver different looks of your subect in front of the camera.
Alweays and especially for this situation you should use some exposure tools like zebras, waveform, histogram and/or falsecolor.
You don't want to burn out parts of your image completely white. The problem of the 6D is that is has only the histogram which makes it relatively difficult to nail the exposure where you want it to be set.
The best way to get a proper lightly over exposed image is using a good monitor with the feature mentioned before.
Also shoot in a flat image profile so you don't have to much contrast in the image that could cause more burned out parts of the image.
Mostly you have your finished shooting script printed on paper in front of you so can mark and make notes into it.
Yes, it takes some time to devide every site of the script into 8 nearly equal eights. It doens't have to perfect. Just use a ruler and a pen to do it by sight.
Dividing a script into eights is just that other people who read the schedule, the shotlist or storyboard find the exact part of the script faster than just having the page number and then searching the line they need to know.
Of course you don't have to do it but it makes life much easyer and it's a part of film pre production. Mostly you don't have enough time on set but more than enough in pre-production so safe you some time on set by spending some time when you prepare your shoot.
Don't slate if it's not neccessary. Don't do dual system audio recording. Do it via XLR in camera. Avoid multicam shots. Don't have gear around you do not really need.
Have your camera on a light weight tripod or (even better) on a good balanced shoulder rig. Have someone around who has an eye at all the gear you have with you. Have enough batteries and media with you and carry them at your body to have them available very quickly.
Prepare as much as possible. Have every shot planed before you get on set. Know the location(s) your shooting at. Don't waste time by developing shots on set. And keep your crew as small as possible but as large as needed.