I came across this book on the (relatively) new Archbishop recently in the Oxfam in Aber the other day and picked it up. It is very brief and simply gives the bare facts plus some interviews with friends. Welby had a rather dodgy background on his father's side but the rest is pretty predictable - Eton, Cambridge, CICCU and Bash camps, Charismatic Renewal, oil executive, study and ordination, rector, international peace promoter, higher office. Over the years he's managed to dabble in high church as well as low church ways and so I'm sure is an ideal candidate for what is wanted. I learned from the book that the Welbys had a daughter die young and that there are more Anglicans in Nigeria than anywhere else. I was also left as bemused as ever by the whole Anglican scene.
Bonhoeffer uses a similar phrase 'worldly Christianity'. It's J Gresham Machen that I want to line up most closely with. See his Christianity and culture here. Having done commentaries on Proverbs (Heavenly Wisdom) and Song of Songs (Heavenly Love), a matching title for Ecclesiastes would be Heavenly Worldliness. For my stance on worldliness, see 3 posts here.