Barb,
A challenge is what foodie life is all about !
My main bread resource is a great book by Dan Lepard, a British baker, called THE HANDMADE LOAF. A lot of the temps and oven times are a bit off, but Dan provides errata on his website
http://www.danlepard.com. He makes the comment on pg 36 "Both barley and rye lack the stretchy gluten needed to hold the shape of a bold, jaunty loaf. But use them with strong white wheat flour, and let them serve submissively as a background flavour, sour with ry and dusty with barley, and you have the perfect, friendly bread."
Having said that, he has an interesting recipe for a 100% sour rye loaf, which involves making a gelatinized rye mix (basically a paste of rye flour in boiling water)first, to give elasticity to the crumb. Hmm...now you've got me going, I might have to try this...better go build up some rye leaven...
Celia