You need to keep in mind you will need a larger ratio of high-gluten wheat flour than low-gluten or gluten-free flour or your bread won't rise. The higher the ration of low-gluten and gluten-free flour, you may need to add Vital Wheat Gluten to make up for the loss of gluten. I mill whole grains/seeds/beans and make my own multi-grain flour and coarse cereal mixtures for bread making and all baked goods.

Word of caution if you use a high ratio of rye flour in a bread recipe, the dough texture remains rather sticky even with the correct hydration. Due to the stickiness it's easy to add too much flour during kneading and end up with a dry dough and a "brick" for a loaf of bread. To help prevent this you can oil your hands during kneading, dip your hands in water during kneading, or knead your dough in a large zip-lock bag (using a method similar to "Bread-in-a-Bag").

The link below is to King Arthur Flour and a nice group of multi-grain bread recipes and they are well-tested.

-Grainlady

My supermarket quit carrying one commercial rye bread, and only kept Robust Rye which I find rather bland.

Any suggestions?

Go with the oven instead of the bread machine?
Right now I've got rye flour, whole wheat flour, bread flour, and corn meal.

If you are not on a salt restricted diet, this rye bread recipe from King Arthur is good for a sandwich. It's light and flavorful. I've used it for years when serving rye sandwiches to a crowd because some people don't like the heavy texture of traditional rye and this is very light.

/tricia