One book that should be on your "must read" list is John Kleinig's "Grace Upon Grace." As you might glean from the title, the book is all about God's grace for sinful people. Reading this book will leave you with a greater desire to give thanks to God for His love for you in Jesus Christ.
Kleinig also uses vivid imagery as he writes and here is one wonderful example: In spiritual warfare, we operate in the dark. We must learn to see with our ears, for here we depend completely on the unseen presence of Christ and His Word. (page 220)