Since there are already various workable user interfaces for Maxima,
what I think would be even more interesting would be to equip some
graphical program with Maxima as a computational engine.
That is, there would be a GUI and there would be Maxima, but the
program is not mostly about providing a GUI for Maxima,
but rather that there is some problem domain and Maxima is an
incidental part of the solution.
Examples could be: a spreadsheet equipped with symbolic
capabilities; statistical analysis; process control; quantitative
financial analysis; mechanical design; risk analysis.
Probably there are changes in Maxima which could help such applications.
E.g. relaxing the "user in front of the console" assumption.
As for myself, I like to have a command line, but I would be
interested to work on aspects of Maxima which make such
applications easier to write.
best
Robert Dodier