I'm not so much a fan of operating accessories. I'm a passenger train fan, so my RR is always operating at a financial loss. A train standing still doesn't helpthat.
Actually, I like the operating "accessories" which don't interact with the RR. Carnival items; MTH firehouse, gas station, etc.; Lionel dealership; superstreets and bumper trolley.
At our club I tend to run the coal tipple when we have shows and I can tell you that kids (up to about age 80) LOVE it and love pushing the button which makes it operate.
So I guess it all depends..........
Gerry