I don't know if you have noticed, but Microsoft introduced new type of lookup field in the customization area.
From CRM 2016 220.127.116.112 we are able to create a regular 1:N Customer connection between entities and Account/Contact.
So we can now really mimic the behavior of Opportunities, Quotes and others...
If you don't see this feature in your CRM, then wait for the update.
Newly Created CRMs already include the latest update.
Happy CRM day,