So now that we have Arnold it's seriously time for a new framebuffer. Talk with solid angle and look at other examples out there but it's really time.
some minimum requirements.
-Save versions and various ways to compare
-IPR mode. if you look at the recent Vray Frame buffer updates you can easily use IPR, stop it and start a production render.
-load LUTs and colour profiles.
-Basic Colour correction
-All AOVs and passes in one window with the ability to scroll through while the render continues.
-select objects and/or materials
-pick DOF focus