Roller Coaster Tycoon Classic was developed by Chris Sawyer, who did the first two games, and then left the games industry for decades, partially because of a disgust with the shift towards violence[0][1]. So in a way, Roller Coaster Tycoon Classic is the first "canon" Roller Coaster Tycoon sequel after the first two games.
Also, the first game was almost completely written in assembly[2]. I don't think one can pull that off without having some really high coding standards, so I'm not surprised that the game runs really well!
I mean... given it's already assembly it should be easier than normal to reverse-engineer it, no? Or do you think there's lots of nasty low-level hacks in there that will be harder to decipher?
I've tried disassembling the version of RCT 1 that's on Steam, and the program starts by, IIRC, decrypting the other parts of the executable before jumping into it.
As far as I know, the version on Steam is the same as what came on the discs with the only modifications being some patches for compatibility. There were also no references to Steam's DRM anywhere
Also, the first game was almost completely written in assembly[2]. I don't think one can pull that off without having some really high coding standards, so I'm not surprised that the game runs really well!
[0] https://en.wikipedia.org/wiki/RollerCoaster_Tycoon_Classic (note that it also has just been released on Microsoft Windows and macOS on September 28)
[1] http://www.eurogamer.net/articles/2016-03-03-a-big-interview...
[2] http://www.chrissawyergames.com/faq3.htm