As to being interactive, Would you have activating devices for the public to start and watch accessories, have cameras displaying action in obstructed areas?
Paradise and Pacific RR Club is a bit unique. We are housed in a 10,000 SF train building nestled in the McCormick/Stillman Train Park in Scottsdale, AZ that opened in 2011. We have 1/3 of the building, an N Scale club has a 1/3, an HO Scale a 1/3 and a Z Scale a nook which is open to the public, (Sans Covid-19), 362 days a year.
The clubs have use of the building by maintaining a layout with running trains and accessories. All of the clubs have IR or sensor activated trains, accessories and sounds. A typical year sees over 100,000 people enter the Model Railroad Building, many repeat visitors but also a large number of tourists.
The McCormick/Stillman Railroad Park web page (www.therailroadpark.com) highlights the park and it amenities, (www.pandprrclub.org) highlights the O gauge Paradise and Pacific RR Club.
There is no cost to the public, The city of Scottsdale and Scottsdale Railroad & Mechanical Society have partnered to preserve a train park with 2 running trains, 1 run by the park (tickets required) and one by a Live Steamers club (donation requested), an historical carousel (ticket required), a Museum of Historical RR items housed in a former Presidential Car (The Roald Amundson) and concession stands amid the buildings, playgrounds and picnic areas. The park is nearly self sustaining with help from the SRMS.
To build, maintain and operate an enterprise as you describe as your "Dream" situation, would require a spot well traveled, be entertaining and well spoken of, not too expensive an entry fee so families would stop and enter. Our club has over 100 members and it is a weekly labor of love to keep it all running, much like your vision would.
I wish you luck if you are able to make it reality, and for the hobby's sake, more exposure is always good.
