>It's all too easy to become the same ego you were before, only now with a spiritual varnish. In my observation, there is a lot of rationalization around this.
Can you think of anything more self-centered and intoxicating then conflating your ego with the "Ground of Being". Narcissism is the cliche sticking point of westerners. Than again Westernized lineages systematically address this. Mondo Zen being a good example.[1]
Historically, Buddhism doesn't export cultural context. It embeds itself in what is already there. Zen exists along side Shinto. Tibetan Buddhism envelopes the local shamanic beliefs. Trying to export the cultural context of Tibet or Japan to the West is a mistake.
[1] http://www.mondozen.org/