Appreciating what our ancestors might have experienced

This relative of mine was age 82 at death; what was his quality of life?

No doubt about it: living a "sheltered" existence is a challenge to us in this modern day.  When I saw this post at the CDC site, I felt humbled at the challenges our ancestors may have encountered!

What other events or circumstances may have played a part in determining how, when, and where our ancestors experienced difficulties, other than disease?  Please add your thoughts! 
 My list includes:

1. Weather or environmental challenges?
2. War, or other calamities?
3. Availability of learning and literacy concerns?
4. Economic ups and downs?
5. How would creating a timeline for the life of your ancestor help you to know more about his story? (Both Ancestry.com and FamilySearch.org have a time line feature; explore and let me know how helpful that is for your research!  Oh, and I think that Billion Graves also has something similar!
6. Where, online, can you post notes that will give a better insight into your ancestor's life?  How about findagrave.com?  At familysearch?  At wikitree.com?  On the site at WeRelate.org?
7. Finally, what kind of impact does a photograph of your ancestor have in learning more about their lives?  What type of forensic investigation does a photo invite?