If you paid for this formula you should demand a refund. Here is what is wrong with this formula:
1) Hair products do not need oils. All the oils you see in commercial products are added at a min amount for label appeal. Cut oils to 0.5% or even less. As long as you have a drop there you can say it on the label.
2) Too much of vitamin E. You don’t need more than 0.2%
3) 0.25% of cetrimonium chloride isn’t enough to emulsify 8.5% of oil. Keep it for conditioning and add a non-ionic emulsifier. Ceteareth-20 will do (GMS+PEG-100 Stearate is another option). How much depends on the amount of oil and Cetearyl alcohol you are going to keep.
4) In a properly emulsified product, 4% of Cetearyl alcohol won’t stay liquid. Cut it to 2% if you want to maintain low viscosity (try 1%, 1.5% and 2% and see what works for you).
5) Sodium benzoate alone is not enough to preserve this product. It’s not a broad spectrum and it requires low pH.
6) They should not suggest a precise amount of citric acid. Citric acid is qs to pH of XYZ. In this case, your pH should be not higher than 5 because of your preservative but I think you should replace it with something reasonable. At least Euxyl PE 9010.