Nice ideas for a future HyperCard...
Okay, so stumbling over that note on BASIC's fundamental design principles kind of got me reading Wikipedia, jumping from one link to the next. Here's a another interesting idea:
Program-by-example: Stagecast Creator (fka, KidSim/Cocoa) basically lets you define simple behaviors for objects (movement, for example). Then you just run the program, and every time something happens that might be interesting, it will ask you what to do. The page lists an example of how you can have several objects, have one walk from left to right, and when it collides with another object you'll be asked what to do, and you can e.g. tell it to "walk around" the other object. It's a very simple example, but I'm sure there's a way to use the general technique successfully in other programming endeavours. AppleScript's "record" feature kind of goes along similar lines... maybe one should combine these two?
A nice practical application of this is in CSSEdit's Preferences, where you edit a code sample and it automatically deduces from that whether you like your brackets on a line of their own, or on the opening line, or... Pretty simple to implement for the basics, because if you know your sample text, you can simply find the characters between the identifiers and then paste them into code when reformatting it.