Hmmm... as an avowed anarchist I must disagree with the I as far as castes/hierarchy being a positive thing (if I am reading you right...?)
Also I was thinking of India with regards to caste (well I was thinking of Guyana too... dunno if you've read Kean Gibson's book "The Cycle of Racial Oppression in Guyana" which I do have some disagreements with but I think the core idea she presents has some merit)... but it is certainly true that caste systems exist and have existed in Africa as well... read Camara Laye's "The Dark Child" regarding the castes of blacksmiths, etc. etc....
I duz always be on the computer at this internet cafe for the half hour after I finish work so I never have as much time as I'd like to get into things but I'll try to roll forward next week sometime and continue the reasoning further... Respect