allow me to add that Buddhism is not a dogmatic, "blind faith"
religion. Therefore, grace is not the deterministic factor to
Nibbana, even in Pure Land Buddhism.
This thought led me to the word faith, which is also not greatly
emphasized in Buddhism as in other religions. But, that doesn't mean
that faith is futile in Buddhist practice.
Many western writers have given Buddhism a new perspective, and this
includes Sharon Salzberg's Faith (ISBN: 1573222283). This may be an
area you want to consider -- the ever evolving globalising Buddhism.
And living in America means that you can easily get in touch with
these contemporary Buddhist thinkers.
As for the word kamma, with right understanding and right effort, all
humans can attain nibbana here and now in their present lives,
regardless of their past kamma. Nina had, in a previous mail, related
Angulimala's story and kamma.