First of all, I'm presenting facts, not defending LaVey and Crowley on a personal level...please remember that. Sorry if I seem condescending...but there are many uminformed opinions in this forum.
LaVey (1930 - 1997) didn't preach Crowley's (1875 - 1947) system...he had his own.
Describing Thelema as Satanism isn't accurate, despite whatever superficial similarities people find between the two Beasts. Describing LaVey's "teaching" as truly Satanic is marginal in itself...but that's for another day's discussion.
Most intelligent people regard LaVey as an entertaining, but ridiculous circus freak...the only people who take him seriously are mental cripples and rock musicians (same with H.P. Lovecraft).
From what you're saying, Satanism is no different than Buddism, which strives for personal enlightenment and doesn't depend on external supernatural influences. Correct?
People use words incorrectly to justify their own uninformed bigotry. "Satanic" means occult. "Democratic" means good. "Fascist" means bad. "I have no idea who Che Guevara was but I have a poster of him on my wall"...etc
You can slam whatever you want, but at least try to have some idea of what you're really saying.
You can find a good essay on this subject (meaning of language) by George Orwell titled
Politics and the English Language. http://www.orwell.ru/library/essays/politics/e/e_polit.htm
There is something to be said for being informed and knowing what you're talking about. Can you give me that?