As a non-participant looking in from the outside, the LDS (Mormon)  church seems to me to be the best-structured as a social service organization.  

The non-payment of clergy; the volunteer work parties for those needing help; the requirement of the able-bodied to help themselves to receive help; the 10% tithing; the requirement to have at least three-month's worth of food for family self-sustenance in the event of an emergency; the two-year mission requirement and the missions for those who have reared their children and still want to serve are the high points of their social service that I have noticed. 

Their historical theology and other beliefs are no stranger than many other religions with which I am familiar and clearly superior to the fanatical Christians or fanatical Muslims.