At first glance your list looked like it'll get totally ripped to pieces by Chaos. But it could just work. I personally think that it could be a strong army against Tzeench in 1k battles. But it will take a while before those RxB's kick in. Why? Chaos has t4 and if his whole army is chosen (warriors + Knights) then youve got a 4+ to 1+ armour save to shoot through. With 30 shots on knights (hitting on ~5s, wounding on 5s and a 1+ Armour) you'll be lucky to kill ONE knight in one turn, and against warriors youll kill about 1 a turn. But you do have manoverability on your side. What i'm trying to say is, just cos all your shots bounce of very very thik armour, just keep trying and you'll weaken him. all it takes is for him to lose one Knight and a 2 of warriors with shields (all Chosen) and youve got your self around 87 VP's. just keep on trying untill you have a very weak chosen unit (half strength) and then charge it with EVERYTHING - 3 Nobles and 1or 2 units of Dark riders. You may begin to wonder if these guys were actually CHOSEN of chaos. But you have to be POSOTIVE you can break them, cos all your troops are impact and will get minced in lasting CC.
regards
Dark Pain
regards
Dark Pain