I wholly recommend adding bread spice to your rye breads. Gives a nice complexity to the flavour profile.
I use equal parts cumin, fennel, coriander and anise seeds, coarsely ground. 10g total per kg bread.
Thanks! I love 100% rye sourdough breads, but I hate making them. I'm not sure I get the hydration right. My dough always ends up very sticky and just an utter pain to get out of the kitchen machine and into the loaf pan.