One benefit I see (that hasn't been talked about yet) is that the D&S and C&TS could interchange equipment and shop resources much more easily with a line between the two. Perhaps create shared ownership of MOW equipment, for instance.
But - I agree that this line's scenery isn't much. If we're talking 150-200 million dollars, why not seriously look at recreating the RGS from (say) Telluride to Lizard Head. There's a LOT of money and tourists in Telluride now, most of whom won't be driving to Durango or Chama anyway (and thus shouldn't compete directly w/those railroads).
The trip to Ophir would be a reasonable length, and the scenery would be incredible.
Just an idea...