Cool idea! Some suggestions:
Use ground sprouted flax seed powder instead to avoid phytate bodies potentially binding with the minerals.
I assume you're using flaxseed oil for omega-3 fatty acids? Use krill oil instead.
Cocoa has the same problem, and is hard to replace in terms of taste. Coconut, avocado, hemp (seeds or oil), acai berries, and nutritional yeast might work in some combination, but can all be prohibitively expensive depending on the intended application.
Adjusting the amount of cocoa should lower the amount of fat intake. For optimal retention of muscle mass, 30-35% of the daily caloric intake should come from protein. If you're worried about gluconeogenesis, I understand, and suggest scaling the ingredients such that you can increase the amount of protein once keto-adapted; hemp seeds have a nice 75-25% fat to protein ratio, and is a complete protein source.
Try stevia leaf powder instead of sucralose to avoid potential adverse effects long term. Maybe xylitol or erythritol if stevia is too expensive.
If you're essaying a final go at inducing ketosis, try doing intermittent fasting (IF) concurrently for increased probability of success. To save time, here's a rough sketch of what that would look like:
If the feeding period was from 12-20:00:
Xylitol triggers insulin release which may be undesirable
Eliezer and I have put together this first pass at a recipe for DIY ketogenic soylent--or, as he prefers to call it,The Mildly Surprising Super Ketonic Dietary Replacement Weight-Loss Fluid - It's Not Food, It's Dietary Replacement Fluid!(R) (I am not in full support of this particular preference...)
So let's play Make a Prediction. It seems more likely to be useful than "free associate with why soylent/ketosis is awesome/stupid". Imagine that Eliezer has around a week's worth of infinite willpower (that can only be spent on resisting food cravings etc.). Further, imagine your crystal ball shows you that a month from now, he hasn't lost any weight. What does it tell you about why?
Ketogenic Soylent v1
1 scoop Gold Standard whey protein
1½ tsp calcium citrate powder
1 tsp creatine
½ cup+1 tbsp ground flax
4 tbsp Hershey’s Special Dark cocoa powder
2 tbsp lecithin
⅗ tsp potassium citrate on day 1, increase gradually to 1tsp by day 5, don’t exceed 2tsp
½ tsp iodized salt
⅛ packet Emergen-C
⅕ cup olive oil
1¼ tbsp flaxseed oil
⅗ cup MCT oil
Sucralose to taste
We might need to add water to get the consistency right.
Pills
1 capsule vitamin D supplement/day
2 Opti-Women vitamins per day
1 capsule MSM
Totals Per Day
Calories: 1866
Fats: 193.5g
Carbs: 12g
Protein: 54g
Fiber: 25g
Biotin 250mcg
Calcium 150mg
Chromium 120mcg
Copper 2mg
Folic Acid 600mcg
Iodine 200mcg
Iron 18mg
Magnesium 75mg
Manganese 5mg
Methyl-Sulfonyl-Methane 1000mg
Molybdenum 70mcg
Niacin 20mg
Pantothenic Acid 20mg
Potassium: 5g
Riboflavin 20mg
Selenium 70mcg
Sodium 3g
Thiamin 20mg
Vitamin A 5,000IU
Vitamin B6 20mg
Vitamin B12 100mcg
Vitamin C 250mg
Vitamin D 1600IU
Vitamin E 100IU
Vitamin K 80mcg
Zinc 15mg