Jeremy, the names listed in Genesis 4, 5, 10 and 11 are the names of ruler-priests, not the first people on Earth. These are typical of ancient king lists, as are the lists of Genesis 25 and 36. All these men are of the Hebrew (Habiru/ 'Apiru) royal priest caste which practiced endogamy and had a unique marriage and ascendancy pattern.
We can’t use the numbers in Genesis to put together your time scheme as they are highly symbolic: Cain (7); Lamech the Elder (77); and Lamech the Younger (777). Paleopathology indicates that the lifespan of ancient peoples living in an area extending from the Nile and North Africa to Turkey and Mesopotamia was about 34 years. This applies to peoples in the Late Paleolithic - 30,000 to 9,000 B.C., the Mesolithic - 9,000 to 7,000 B.C. and the Early Neolithic - 7,000 to 5,000 B.C. This would apply to all the rulers listed in Genesis, although rulers tended to live longer than the average people.