Isn't it fair that the two largest parties form an alliance?

The Mumbai election has thrown up a hung verdict with Shivsena getting 84 seats , BJP getting an all time high of 82 seats and Congress 31 seats followed by others..Ideally , I feel that the two parties with the largest support base shd form an alliance not just in this case but in all such instances. It is only fair that people's choice be given some credit rather than let any horse trading take place between parties that have been given minimum amount of support by the citizens..I feel that this shd be made into a law so that no political party is deprived of its right !