hah looks pretty cool but I don't think a touchscreen can replace a controller. also ftr I don't not like virtual instruments, it's just that I prefer playing guitar at this point :)
in the 90s I made a 3d engine because that was the thing people did... then I modernized it about 10 years later (C to C++, 8bpp palette rendering to 32bpp RGBA, multitexture support, etc). And had a lot of fun writing AVS for Winamp, other visualizations, also REAPER video processors and stuff.