I would categorize the show within best of the decade , personally recommend for new anime audience, the pace of the show fits with the story being told.
I agree with the comments on the philosophical part.
It is very refreshing to have a adventure/journey type of anime that doesn't recycle most of the plots being released now.
The protagonist Fushi does his best to achieve his objective, have no time to sidetrack on other matters and show genuine care on saving humanity, even those whom had labelled him as a heretic.
Much love for the character.