[cycomachead]

The idea is to be able to easily move someone from beginning features to more complex stuff. The APL functions are new, but in the past this meant story-based projects to using tools like lambdas, map, filter, etc. When done as part of a course, it's definitely something students can learn.But you can do everything in Snap! without those features, too. (The FOR EACH construct for example works just by dropping in a stack of blocks, but you could choose if desired to pass in a lambda and do different parameter binding...but not many people really do that. ;))

We've played around with various ideas for how many blocks to show and it's definitely a work in progress constantly, but the current design is because most people are using Snap! in the context of a course where there's a push to learn those tools and so they get used pretty frequently. :)