What if they design it for high end buyers?

This is a long term project. Probably a 30yr + project. So the current economic state is of little significance. Note that nairobi CBD sits on 250 acres while Northlands has 11,000 acres. And there is no one else who has 11k acres of land next to the city where the city can expand to. In the next 10-20yrs the westlands corridor, ngong road, mombasa road commercial areas will be exhausted, while runda, karen etc residential areas will be full and thus northlands will be the place to be.

It will be a PPP (Public -Private -Partnership) Project wherein the contractor designs,builds,operates and maintains the road at his own cost(while recovering his money) before handing over to the client.

Now that Kenya-1 has Nairobi City under his control is there a larger plan to expedite Northlands City before His term is over?

Kenya-1 would wish to expedite N-city plans, but there is a problem. No money to pay Civil Servants salaries or for loan repayment leave alone to be misappropriated.
Heck! and no one is willing to led any more!!.