Eluvatar:
Except the Security Council has no legislative power. What you're proposing would reduce democracy.
Actually, it wouldn't because if an RA member meets certain requirements for the 'upper house', they automatically move to the upper house (Senate/Lords) and vote there instead of in the lower house (RA/Commons).
The advise and consent practice in a bicameral legislature would permit a more orderly construction of bills (each house representing certain elements in a democracy - that being influential vs. non-influential nations).
It allows for and encourages nations to remain active and gives them a competitive incentive to move to the upper house. This, in turn would also cause the lower end of 'influential' nations to slip back into the RA if they cannot compete in terms of influence in comparison to other nations in the legislature. The ultimate result would be an increase in the influence and security of the region because it would produce a larger general population of nations, more influential and hence more difficult for a rogue or invader to expel from the region (and hence paralyze the government). It also produces a merit based system in which people can actively improve their position and level of merit.
I've thought about this carefully for the past few days. If we want activity and activity that is consistent and lasting, we need to bring competition into play and eliminate static blocs of power that remains in the hands of just a few people.
Essentially, reward activity and accomplishment and encourage others to be active and encourage them to accomplish something by attaching merit to their actions. If people have no hope of participating because the same people always maneuver themselves to the to and stay there by excluding others from that 'elite', people give up and leave.
IOW, any form of 'power elite' should be replaced with a competitive system in which people can climb the 'social ladder' and power structure without being excluded permanently by a self-regulating, self-appointing and self-governing small group of nations because the existing structure only squanders the talent available here by not taking advantage of it.
See where I am going with this?