I also will be glad to see some simple thing in future version of IN:
1. rotate by any angle
2. crop the image
3. resize (upscale and downscale) output image (it can be standard methods: nearest, bilinear, bicubic and lanczos3)
4. improve contast and saturation by the curves - one field with curve and 3 menu points: contrast improving in Y channel and saturation in Cr, Cb channels (it is important in the case of IN because noise reduce not only detals and overall appearance of the image but colors and contrast also).
5. some work with EXIF data like add comments "Filtered with Net Image version 5.8 and user made profile by UserName".