So in other words, you ran a 40k game? :D
I mean let's be honest, there's a reason they had to do a massive retcon and go "Oh no, Abaddon isn't the most incompetent idiot of all time, he didn't really get spanked every single time on those last dozen crusades, in reality they were a great success, really! You all just didn't realize the genius of his grand design!!!", I always thought Chaos being immensely powerful and only failing to roflstomp the whole galaxy because time and time again all its servants are massively incompetent idiots is kind of the core concept driving the whole conflict.