Given the bad location of 2J on US 71, and the mainline is together between 10th and 11th, I'm pretty sure that US 71's points are victims of point drift and I fixed other routes without fixing it.
As for the interstates in Council Bluffs, those are intentionally NMPs following the creation of the dual, divided freeway. Technically, the inside lanes are ONLY I-80, and the outer lanes are I-29/US 6 with local I-80. I am open to the idea that they shouldn't be separate, but since one can follow 80 straight through and not be "on" I-29, I think they should be. (The necessity of double-travel to clinch is noted.)