Thanks! A2 is a modular synth with realtime scripting (with A2S) - which at this point, is the only user interface. (Documentation in progress: https://github.com/olofson/audiality2/tree/master/doc ) The idea is to cover everything from virtual instruments through sound effects and streaming with a single architecture, in order to eliminate the traditional distinctions between these fields. A2S was never really intended as a "music language," but that's how all music for it so far has been authored. Dynamic/interactive music would seem like the obvious next step there.
Either way, I'm planning on building an interactive A2S editor with tracker capabilities, and possibly support for "instrument" GUIs for realtime tweaking. Wrapping A2 up as a VSTi for music authoring in traditional DAWs is also on the list. It has crossed my mind to do something more similar to the FMOD and Wwise authoring tools for A2, but that's a massive project, and I'm not sure I want to develop and support tools full time. But, you never know... :-)