I pretty much agree with you, Greg.
However having a second caboose at the end of the train is not all that bad, IMHO, as cabeese
were deadheaded occasionally. I remember seeing two cabeese on standard gauge freights when
I was a kid, and I'm pretty sure I've seen photos of two cabeese on the D&RGW narrow gauge.
But three cabeese, especially with one or two directly behind the locomotive, was limited to railfan
excursions.
Using an old rider boxcar or two at the rear of the train doesn't detract too much from its over-all appearance; I would recommend this in lieu of coaches if any are still serviceable, especially for your option #2. Careful selection of photo locations can "bury" the rider gons and boxcars behind a curve or some trees - with the caboose(s) still visible - so authentic-looking photos of the front of the train are still possible.
As it's becoming more and more expensive to run special trains - primarily due to rising insurance costs - hopefully some way can be found to encourage chasers to chip in. I have done so in the past and would do so to an even greater extent in the future if the trains looked reasonably authentic ...
- Russo