I would disagree with your statement about psychology and the abcence of its involvment in Satanism when you look at the "lesser magic" of Satanism. "Lesser magic" is, basically, Psychology applied to real life situations.
I would agree that Satanisms symbolism would appeal to a slim minority of the population, which, I feel, was the reason LaVey adopted it. He is, I think, using taboo symbols to ward off those who do not have the understanding to see the point behind his message. After all, the CoS website states on their welcom screen they are "Looking for a few outstanding individuals."
I agree that Satanism is a "psychological retrobution game" with christian imposed social norms. And I think its about time.
I think LaVey himself, would agree with the statement that what he wrote was not new. He says in the Satanic Bible that the
Meta-Tribe always has existed and, in some form, exists in everyone. He simply attempted to give symbol a name to it.
The best explanation about the Enochan keys being printed I can give is that LaVey intended their to be a "willful suspention" of ones beliefs about reality and intentionally adoption of the fantanstic. The Satanist intentionally uses fantasy to fulfill the psychodrama necessity that their human ego desires. No Satanist really is praying to anyone or anything when they recide The Keys, except their own emotions and mentality.
And your "secular Humanism" interpratation is right on in my opinion. Really, thats was Satanism is, just placed in a religious context.
I am leary about seeing Satanism as "obsessed" with Christianity. Many of its symbols are devived from different herecies of the christian church, (Baphomet for example), but then again, there is a Call to Cthulu in the Satanic Ritual... and last time I checked, H.P. Lovecraft isn't consitered Christian Cannon. haha.