GNUitar seems really interesting, expecially 'cause has a Win port (hope to see it work under ReactOS - http://www.reactos.org - and Haiku - http://www.haiku-os.org - too in the future).
Here are some other software that could help you to upgrade your software (I suggest you to try to involve authors to build an "open source GuitarRig alternative!):
Last (but not least) i suggest you to keep in touch with Frets on Fire (http://louhi.kempele.fi/~skyostil/uv/fretsonfire/) devs, that can be interested in supporting you.
HaPpY CoDiNg !!!
can you make it so my mouse wheel moves the sliders by 5% per click or even 2% a click? some of the sliders i can only get a very very rough, or very very fine tuning on the sliders. second, can you install an overdrive effect? third, can you add a flanging effect? i love the program, its probably my favorite guitar prog for linux yet. its easy to use, easy to install, but most of all, it works at the end of the day.
can we get some "tap tempo" and "reverse" delay going? i like a tuner that can play a 440 tone, but ALSO be able to tune "lingot" style. i like to be able to tune both ways.
can you add an octiver, and pitch shifter? i would also like a few more distortions to choose from, and multiple over drives to choose from.. THANKS!!!
it would also be nice to have a module.... to say control the tone of a guitar. my friend has a guitar with out a tone knob. it would be nice to be able to select between different emulated tone capacitors. some guitars have .022 uf capacitors, some have .033 uf capacitors, and others .047 uf capacitors.