Thank you, those are great.
I really like
Grace Celeste, but I think it's a bit short. Does
Grace Celesta sound odd? Yes, I've just realised it rhymes with molester. ;)
Grace Isabelle is nice too - I would spell it
Grace Isobel, though. That doesn't look as nice, but I can't stand to spell it any other way, don't ask me why.
The other I like is
Grace Annabelle, though, again, I would bring it down to
Grace Annabel.
What do you think of
Grace Vivienne? (with stress on the "enne")