You can import other notebooks and break them up, the tarot one did grow a bit big. I prefer observable to replit because observable is JavaScript running in the authorative JavaScript environment (the browser) which means you can debug your program with state-of-the-art tools whereas replit is a proxied interface to a container with a simulated debugger. Normal Industry JavaScript stuff like
sentry.io,
replay.io just works with observable whereas replit has to manually backport everything so I can't get behind the engineering choices when thinking about optimizing DX.
Replit you need to provision a container but observable works with ephemeral federated compute that I think is the future of computation. I think the web is the future for everything though, that might be optimistic :p JS does suck and machine learning and other important things, replit no opinionated runtime options is pretty nice, but I just love DX too much