Integer "blending" and stencil value from texture.

This first suggestion should be quite low hanging fruit:

For depth stencil textures, provide a direct way to get the stencil value from the texture. (There is a really old nVidia extension GL_NV_copy_depth_to_color that lets one copy the stencil to an alpha channel, but, sill to have to do that).

The second suggestion, I am not so sure it is even possible on current hardware:

“Blend support” for integer render targets, probably not identical to what we have for decimal (be it fixed or floating point), but most of it (like drop ONE_MINUS_WHATEVER).

Together with GL_NV_texture_barrier, one can then do some additional interesting deals with integer targets (where as now they are limited to just logic ops).