As for your NR1, NR2, NR3 scenario, I have some points to make.

1) These deals would be a lot of hassle for a volunteer position.

2) The small size of the electoral district makes it difficult for any party to organize over many neighborhoods.

3) In all political parties, there is a lot of infighting, much of it is never reported in the press. While a few deals will be struck here and there, it will be hard for a unified force to consistently vault its way to the top.

4) Political junkies who like to see or participate in all this maneuvering are far from majority. Many citizens want government to be the background of their lives. When they see the TDG working well, they will be happy to cast their neighborhood vote once a year.

5) Trying to build support when the first and probably second tier really don't much to offer materially is another reason for dealmaking not to find much sucess.

The TDG elections are annual. So if any representative at any tier starts behaving no longer worthy of the position, the next election is only a few months ago. There is no need for all the drama to recall or impeach anyone.

The representation at several tiers is indeed an issue when the TDG is three tiers or higher. Should the third-tier representative hold on to the first-tier job as well as the third-tier job? Yes? No? I see pros and cons for both sides. A lot will depend on how the TDG designs itself. So this is something I will leave to builders. The constitutions can be written to accommodate either scenario.