With extensive LUT support in alternative RAW processors I wish Lightroom also had the ability to implement LUT color correction directly with a section of Develop module. The simpliest way as I see it is to have an option to select LUT .cube file and be able to change its overall effect on the image with a transparency or percentage slider. I can do that in Photoshop with Color Lookup adjustment layer; I'm also aware of creating a custom color profile based on a LUT with a percentage slider. The latter workaround is cumbersome and tricky.
Having a separate LUT section like Split Toning would immensely improve color correction within Lightroom. Furthermore, having the ability to load more LUTs as a stack with different effect would certainly make LR a killer app.