Although the general impression of Kitaro's music is that it consists almost entirely of undifferentiated space rock synth noodling, the truth is actually a bit more interesting than that.
(Which is not to say that there aren't sections of The Sacred Journey of Ku-Kai that sound like someone taped down random keys on an old synthesizer and then went to get a cup of coffee.) This lengthy piece of program music features plenty of real instruments, particularly woodwinds and percussion, along with bits of birdsong and other nature sounds.
Later in the album, unexpected elements like some old-fashioned prog rock electric guitar (on "Flow" and "Evening Sun") and even the out-of-nowhere appearance of a full choir of Buddhist monks ("Nen") add further interest to the sound.
It's still an uninterrupted bliss-out, and anyone who requires such subtleties as melody and rhythm in their music will be driven insane, but there's more to The Sacred Journey of Ku-Kai than the previously uninitiated might expect.