I have the Chronicles set and enjoy them, part of the enjoyment being the opportunity to see the development of Martin over the years and how his work reflects the times the work was made.
We might not "buy" some of this work if issued new now, but this is a musical biography and to leave out the lesser tracks would be like bad editing. They are a part of our history and even the "bad" sounds pretty damn good to me!
How many other artists would you listen to with a repertoire that has evolved over 36+ years? And I have never noticed a "cod" rural accent, but it's preferable to a phoney American one.
The set isn't really issued with casual buyers in mind, just as most exhaustive sets aren't, more for fans who want to know as much as possible about an artist's origins and influences. MC fans will love it, others who are mildly interested won't be disappointed either.