Why doesn't New Mexico assign exit numbers to unnumbered interchanges?

[DJStephens]

"They" did add a center concrete double faced barrier (CBR) wall three years ago.  From the eastern edge of the Exit 6 interchange extending up the hill to the Rinconada overpass.   Before, there was just "mountable" median.  They also added double cable barrier all the way to the eastern end of the section (Baylor Canyon/NASA Road) interchange at that same time.   Where only field fence existed before.   The cross section immediately E of Exit 6 has six lanes on the main lines.  There needs to be a Full Left shoulder there.  Eliminating it would feed into this culture and mindset of regressive design which is all too omnipresent here.

I know; that upgrade from Del Rey to Rinconada was done around 2016. I was saying that they could make the rest of US-70 six lanes total using the same approach without having to move the frontage roads. Of course, they'd just have to add a center span to all of the bridges since they were built as two separate structures with a gap in the median. There's enough room in the center median of US-70 and the buffer between the mainlines and the frontage road to add two more lanes - as long as a concrete barrier is used in 3 places: between the mainlines, and between each frontage road.

There is a reason another prominent poster on this site referred to US - 70 in East Las Cruces as a "third world expressway".  The horrible decision making in the "design" process as part of the Gary Johnson / Pete Rahn regime.  And no, it hasn't improved since.   Most of the interchanges built during the '99 to '04 "project" were shifted at least 6 feet off the pre-existing mainlines.   As one travels E from I-25 all but one of the interchanges were shifted.  Holman / Dunn believe was the only one that wasn't.  Observing the project back then, am of belief a six lane cross section should have been built E to Mesa Grande.  Filling in the median, to allow for a third lane in each direction, would also allow for "fixing" the earlier blunders of the "shifting" by widening to the outside on the S shoulder, to correct.  Looking back, retroactively, would have widened the cross-section, to have included the high tension line, which was strangely "preserved" along the southern edge of the ROW.  It should have been moved - either underground, or to newer galvanized towers constructed in a wider median. Ideally, the EB frontage would have been where the high tension line is now.  In short, would have spent more, then, in anticipation of future growth.   
Given possible, and factual growth patterns, that have indeed come to pass, the nineties decision making was indeed not well thought out.   More confirmation that "planning" in this part of the country is near non-existent.