I have to admit that a very long time ago I had even loftier goals than
that:
Given how easy it is to introspect both Python as well as XML, I thought
about having an applet (wizard) that would provide guidance through the
whole schema as well as TAL template creation process.
In other words, instead of simply providing basic 'yes'/'no' choices, it
would allow the user to interactively design the schema, and then design
a basic web (TAL) interface for that.

Anyways, obviously that never materialized, and I'm not sure how much
time I will have to help with that. So, take this as a simple suggestion.