I am not a natural rabbit (hmm, several meanings to that) but if I have to eat rabbit food then I like watercress, and spinach, and as a mixed leaf salad, spinach watercress and rocket. Coriander leaf does indeed taste like soap and I believe its old English name was "soapweed".

Any salad is improved by a mustard, olive oil, and vinegar dressing (maybe with some crushed chilis shaken in).

That dressing works well with avocados too. I'm not sure what "avocado" is in American.