I agree on all points,
I did not intended to compare pTk vs. Gtk2 vs. Tcl::Tk (this time:), rather I wanted to mention a way of factoring out GUI and separating it from logic.
but I probably have lost control of myself :):)

addition WRT pTk vs. Gtk2 vs. Tcl::Tk, usually it goes differently: when pTk vs. Tcl::Tk are compared then people explain that Gtk is even better and finish reasoning :):)
(although pTk and Tcl/Tk have very much in common and Gtk is very different)
BR,
vkon