Yes, Vega is trying to serve multiple goals. A primary goal is indeed to make it easier for programs to make visualizations. Doing so also creates the opportunity to write new higher-level (and perhaps more user-friendly) generation tools. Possible examples include higher-level grammars like ggplot2 (Vega is lower-level but more expressive) or using Vega as a file format for visual, interactive design tools (an ongoing project in our group at Stanford).
In talks with journalism school instructors and others we've also learned that many novice programmers found models like Protovis easier for students to learn and use than D3, and JavaScript issues often dominated toolkit-specific issues. Our hope is that Vega proves simpler for a variety of tasks; that has certainly been our own experience so far.
That said, your post points out that the messaging on our website may be miscalibrated. We'll consider and revise appropriately.
In talks with journalism school instructors and others we've also learned that many novice programmers found models like Protovis easier for students to learn and use than D3, and JavaScript issues often dominated toolkit-specific issues. Our hope is that Vega proves simpler for a variety of tasks; that has certainly been our own experience so far.
That said, your post points out that the messaging on our website may be miscalibrated. We'll consider and revise appropriately.
For more about the specific motivations for Vega, read https://github.com/trifacta/vega/wiki/Vega-and-D3
Thanks for the feedback!