How quickly the AI gets "mad" at you and declares war seems to be related to whether or not your competing for living space as well. If Since most races are Rock, if you pick Ice they are less likely to view you as a threat..
I always seem to choose ice.
The only advantage I see is that you don't waste so much time colonising and get down to the fun stuff of blowing things up.
Askan
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It should never be forgotten that the people must have priority -- Ho Chi Minh