The note from the author states (quote taken from the website http://www.cloudofwitnesses.org.uk/about/).
These studies aren’t claiming to be the definitive final world on a biblical character, they are a starting point, a way to begin to think about our fore-fathers and fore-mothers and see what we might learn about following God from them. We also want to say that exclusively doing character studies isn’t the best way to handle the Bible. There’s a lot more in Scripture than just narratives, like law, letters, worship, & wisdom! Our recommendation is that you use these resources alongside other things and get a ‘balanced diet’ of Bible study.
We hope these resources will inspire you to do your own studying, to dig in the Bible, learn about God, find your own heroes and, ‘Run with perseverance the race that is before you’. (Heb. 12.1)
Here’s the A-Z so far: http://www.cloudofwitnesses.org.uk/az/