I used to enjoy going to the Bluebell 20-30 years ago, when it was just Sheffield Park to Horsted Keynes. The train service was sufficiently frequent that it didn't matter when you arrived. The service with two trains one way, two the other, worked well for maybe 10 or 12 trips to choose from. The 15 minute journey was quite adequate, bearing in mind you have to come back as well. Time to go round the sheds, look in the bookshop, and the rest of the family didn't get bored with it. If there was a significant event, with stalls at Horsted Keynes, you could spend as long/short as you want and hop the next service back. Short trains and lots of them. Foreign family visitors liked it, we could mix it in with Sheffield Park House gardens, and a pub up in the Ashdown Forest in the evening.
Nowadays it's a big long haul with lengthy but infrequent trains, which no longer suit the historic smaller locomotives, and in fact I've never done the full length, we got off at a passing point, hared over to the opposite train, and rode back. Otherwise get stuck there overlong. It would never occur to us to fag over by train to East Grinstead - we use the train in London daily so that's no novelty. It's just become too tedious, especially with children. Guess what, we don't go there any more.