I think it would be a shame if custom scenery/rides etc aren't officially supported. It's, as other people have said, a very important thing for longevity of a game.
I personally hope that someone will create a scenery set containing construction items (like vehicles, barricades, tape to cordon off unfinished pathways*, cranes...).
That's one of the only custom scenery items I downloaded in RCT3 for some reason.
(*Tape that guests can't walk through, that is. Not like the one I downloaded for RCT3 which didn't actually stop people walking right through it).
I personally hope that someone will create a scenery set containing construction items (like vehicles, barricades, tape to cordon off unfinished pathways*, cranes...).
That's one of the only custom scenery items I downloaded in RCT3 for some reason.
(*Tape that guests can't walk through, that is. Not like the one I downloaded for RCT3 which didn't actually stop people walking right through it).