Do any of you guys know why Eko was killed off? Did he have other projects after Lost or was it always the producers' plan to have him on for a limited number of shows?

Do you guys feel there was something important he accomplished before he died, and that's why he was no longer needed? He pointed out that there was heroine in the Mary statues, he provided the missing piece of the DHARMA Swan Orientation Video, and he dealt with his issues with his brother. So was his job as a character done once he had accomplished these things? Is that it?
Maybe he was too much of a competitior with Locke for "Islands Most Spiritual Lostie"? And he was taking too much of the focus away from Locke?

Thoughts?

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