Seasonal ladder set to 0% luck
The seasonal ladder is played with 3 armies on neutrals. You need to take these with 5 armies each, cause you can't afford one more army on them. The succeed rate however is 94%. If one crucial overtake doesn't succeeds, then you are doomed and will most likely lose the game based on that. 0% luck rate would mean, you take over 0.6*5=3. So you would get 100% succeed rate, like we wanted. The impact of 16% compared to 0% is very minimal, so I would say this would only improve gameplay.
The new season, Season IV, now uses almost completely luck-free settings! See the announcement here: http://blog.warlight.net/index.php/2012/06/season-iv/