It would require extremely minor track improvements to run the train up from Belen to Albuquerue (the wye needs rehabilitation, that's all). Running along the Wichita - Amarillo - Clovis route, *with* Albuquerque, would take about the same amount of time as running along the current route, and have a lot more online population.
The stops which would be lost east of Albquerque and west of Garden City, KS are pretty much nothing, some of the lowest-ridership stops on the entire system, especially now that Santa Fe has the RailRunner connection to Albuquerque. The occasional Boy Scout trip doesn't amount to much. However, Garden City, Dodge City, KS, and Hutchinson, KS have significant ridership and would be a serious loss.
If I had a free hand to design the route structure, I would run the Southwest Chief via Wichita, Amarillo, and Clovis, and Albuquerque; then I would run a train from Denver to Pueblo to Garden City, Dodge City, Hutchinson, and Wichita, and onward to either Kansas City or to Oklahoma City and Fort Worth. But that's a fantasy map. :sigh: