It is my opinion that the 'occult' aspect of the song is over-stated. The occult doesnt run right through the song, theres a tiny mention of "Kether To Malkuth" which Bowie probably tossed in to keep his fans wondering 'what the hell'?, but ive explained this anyway, going from Kether To Malkuth means becoming one with the divine, on earth. And all the biographies mention the 'occult' and Bowie tosses them a few red herrings about stations of the cross and King Arthur, i have to admit its a lot more fun to over-mystify it, but id rather keep it simpler, or it would go off the rails (Pun unintended), IMO. It has to be consistent, it is after all, only one song, although a long and glorious one.
Oh and yes, i am interested in reading your interpretation on "its too late".