I have a solution give random chance to win a castle on hitting down, 70%+/- 15% when hitting 90% of your KS, 50%+/-20% when hitting 70% of your KS and 20%+/- 10% when hitting 50% of your KS, maybe the numbers get tweaked a bit but this generally seems fair.
You can include this with the lower troop losses ideas from above also.
