I'd like to - while I don't hold it in the same esteem as Khan, I do like the Motion Picture a lot. It's had an interesting release pattern, what with all the director's edition business and all, but a strong theatrical release could be made from the current Blu-ray together with the digital stereo from the 1991 laserdisc: http://www.lddb.com/laserdisc/11219/LV8858-2WS/Star-Trek-I:-The-Motion-Picture-%281979%29
While I have the Blu, I don't have that laser. Let me investigate further...