Maybe checkout http://diy.soylent.com, some guy made a webapp for you to come up with custom soylent recipes. I made a variant based on Keto chow and it's pretty good.
Thanks for the link -- I remember spending a good 10-15 minutes before giving up on the DIY suggestions. There were a few recipes that piqued my interest, but most seemed like a chemical sludge. And since I don't live off soylent, I figured it was too much effort to invest the time/energy in a drink that I consume maybe once a week.
Check out superbodyfuel.com - they make several formulas of Soylent-style recipes, and cover different macros and allergen avoidance.