As one who sees a potential route from Chicago to Texas via a stop in St. Louis, this does create a viable corridor to consider, especially to skip tolls in OK and that worst part of US 69 North of I-40 with way too many stoplights. Here's hoping the AR does eventually extend this to Texarkana so that there is another viable alternative to get to Dallas... I'm not holding my breath on any extension of I-45 or Interstate overlay of US 69 in OK, though desperately needed it is.
From St Louis, from what I heard, US 67 is a faster routing to Dallas than I-49 or US 69.
Looking at the map, that may be. Of course, that route would benefit from the upgrade/extension of I-57... and even more so for any Chicago to Texas route, for that matter. That said, and to keep in topic, at the very least, it does give one more Western alterative that avoids any current two lane sections and provides a way to avoid Muskogee and its seemingly dozen stoplights or so. US 69 South of I-40 generally is more open with less stops than the section North (plus, avoids a few of the more notorious speed traps). Nonetheless, this is a good alternate route to have open, and thinking longer term, once AR finishes the Central portion (which may be a while), will provide a better alternative from MO to TX.
Yeah, I see I-57 getting done before I-49 in Arkansas due to cost, mileage, and terrain. Here's hoping that Missouri turns its attention to their portion now that I-49 is functionally complete there (Bruce Watkins Dr.)
While a full interstate would be best, this corridor would be served just fine with an expressway from Poplar Bluff to Walnut Ridge. US 60 between Poplar Bluff and Sikeston is an expressway and there's little push to upgrade it beyond a few more interchanges. I drove US 67/I-30 from St Louis to Dallas a few years ago and there was little traffic from US 160 to Pocahontas both ways.
ADT from Arkansas's web site is 5-7K. I don't care whether Arkansas's portion should continue along US 67 or closer to AR 34/90.
I don't know if it's any shorter, but I-44 in Missouri is hilly, has a lot of truck traffic, and it's not unusual to get caught behind trucks because one is passing the other going 1 mph faster up a hill. US 67 through Park Hills is just as hilly, but has almost no truck traffic and moves pretty fast. Once south of Poplar Bluff, it's Mississippi Delta-flat until Little Rock. I'd recommend the US 67/I-30 corridor STL-Dallas over other routes.