What private market product does not currently exist that should?

Peter Thiel has a section in his book, "Zero to One" which ponders the question asked above but in the context of technology company building.  This site has a ton of smart people with different market vantage points; what are some private market strategies that you feel have massive opportunity sets but no one (or very few/not enough) people are capitalizing on?

A couple from me:

-Growth Equity for Bootstrapped Family Businesses: There are numerous highly successful family/founder-owned enterprises in the US.  In order to get capital to grow their business they either, sell a majority stake to a PE firm, (losing control of their company) or go the debt route which is not very favorable in today's capital market and even more so for a likely conservative business owner.  There are some groups I know trying to do this, but it seems like this category has potential for the right kind of investor.  

-Equity Financing for Independent Sponsor Deals: I know several groups who play in this space, but it is very undercapitalized.  Going the family office or institutional investor route is painful when speed is the difference between getting the deal done and not.  Surprisingly, nearly half of PE deal volume is from independent sponsors.  I can't remember the exact returns off the top of my head, but though volatile, outpaced the performance of the median LMM PE shops.