I've played many games being each of all the three possible sides. I've won in all positions although probably the hardest was being the independents in the three player game.
May I suggest you subscribe to the gloranthan boardgame mailing list and ask the question there as well (plug: I administer the list). Send a 'subscribe' message to 'gloranthaboard-request_at_issaries.com.au'.
Cheers
Robert McArthur
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