I use a farily simple system that has served me well for many years.
I use the milk carton type boxes with Pendaflex folders.Each folder is tabbed with the name of the individual, birth date and death date.All the tabs are lined up in the first slot, so that each individual is easy to locate. Any information related to that individual is stored in that folder.
Any newspaper items, old letters, etc. are treated with Wei'to first to prevent any firther aging.I also will use the manilla folders as well within the pendaflex folder to separate significant items