Have you not come across "meal replacement diet" (which may be partial or total) until now? There is a bunch of articles about it in Google Scholars, not to mention the popular media.
The meal replacements I've seen look a lot more like regular food than Soylent does.
Rob Rhinehart's food replacement Soylent now has a crowdfunding campaign.
If you're interested in one or more of these benefits, send in some money! There is also a new blog post.