It would be nice and very useful to implement support for images to be used as input for samplers. The way I picture it is that you put an image within the folder of the shader and it's filename will automatically be loaded as uniform.
Also since this requires sampler2D, it would be nice if there was iSound and iFreq with both channels combined as sampler2D, it would make porting of sound enabled shadertoy shaders much easier as I wouldn't have to combine these channels in the shader.
I am not sure how exactly shadertoy implements iChannel0 audio but it seems it has something to do with those peeks

