King Bharat of Hastenapur didn't brought the system of making kings just by the lineage. In fact, he didn't find his nine sons fit to be the king of Hastenapur, so he appointed someone else (Bhumanyu) from his kingdom to be the king. This was the justice given by king Bharat to his people. He put a fine line between karma and birth and he called Kurukshetra a Dharma-khestra. Karma was given an upper status than birth in the great Kingdom of Hastenapur. A king must poses certain qualities, if he doesn't have these qualities, he is not fit to be a king.
How can I accept Paras as my king? I cannot accept a drug addict to be the ruler of Nepal. How can Paras give justice to people and Nepal whose consciousness is always deluded by tranquilizers? When birth is given an upper status than karma, corruption starts that very moment. The kingship had to collapse in Nepal because it was becoming too corrupt. Looking the present scenario, Nepal looked better when ruled by king Gyanendra, but it was no good than Rana Regime. Ranas established schools for themselves and gave way to Nepotism. Gyanendra was establishing the same Nepotism and Chakari Pratha in Nepal.
Kingship and Democracy both works when people understand the meaning of these words. Kings in Kingship and Ministers in Democracy must adhere to the duties given to them by the people. Kingship works when there is a force to check kingship; democracy works when there is a force to check democracy. Both system fails when birth is given an upper status than karma.
When Chanakya was about to make Chandragupt the new Samrat of Magadh Kingdom, the so called upper caste Brahmins opposed the idea of Chanakya because Chandragupt was from Maurya lineage, a caste considered unfit for the status of king. But Chanakya explained these Brahmins that Purusha Sukta doesn't discriminate any Varnas saying this is superior or this is inferior. Such is the history of Vedic culture where Karma was superior than anything. "Karmanyavadikarestu ma faleshu kadachana" : You only have rights to perform actions here, you do not have any control over the fruits of your action. (Bhagavat Gita 2.47)
