For proven cheaters they should have the label on the IGN and not able to play, but account stay active. Next any player is allowed to strip the entire kingdom of its contents. First trophy and gold would go then vouchers/ pearls/ gems. Then inventory/ Pals all way to towers blockades and even levels of buildings. Blacksmith slots, inventory slots, wave slots and so on. You could only get what your level would give in game. Also the last path and defense would be left until the end. Players that were in same alliance would be excluded.
Oh one last thing, during the last winning 100% raid when nothing is left there would be a detonation of entire kingdom that player would see and get 100% Treasure Chamber filled.