I think something like that would be very useful.  There are several
good sequencers that have well-developed graphical user interfaces. 
They make it relatively easy to organize events and can be a good
compositional tool for that reason, in particular when things get
complex.  Being able to control Csound would extend their usefulness. 

Job van Zuijlen 

Richard Bowers wrote:
> 
> [snip]
>
> If this were possible, using the 'mapping' method, you would at least be
> able to draw on the functionality of good sequencers (they are, after all,
> pretty good graphic editors and offer a wide range of event filtering,
> graphic input, patching functions etc.).
>