All impractical, but fun to think about.
Narrow guage the Creede branch and run #40 & #44 from South Fork to Creede.
Drawbacks:
-Creede ain't to friendly
-Lots of work and money to re-guage & fix line
Run GTL equipment on reconstructed RGS & Ouray Branch trackage.
-Probably not enough un-obstructed grade to build on.
Rebuild SN RR from Silverton to Eureka. A ride for those who want a shorter trip than the Silverton. (Access to D&SNG shops ...)
Rebuild Gunnison to Crested Butte, run a NG ski train with a rotary (loan from C&TS).
Convert to narrow guage:
Parkdale to Salida or
Salida to Leadville or
Leadville to Minturn
Come to the Springs, convert the Gold Camp road to a narrow guage RR.