I'm a straight up old school player, but at the same time I'm a bit of a geek and didn't let the personal computer pass me by.
The ultimate trainer would be "heads up LCD" a cue with a blue tooth device that senses the position of the cue, direction, as well as vertical and horizontal axis of the cue embedded in the butt. Blue tooth would transmit info to the users base device and LCD screen.
This would be coupled with an LCD screen head gear.
You would get down on the shot with bridge and cue in position use the lcd to lock on the cue ball then the object ball then the pocket. The computer would then calculate the necessary cue position to pocket the ball, lock on tone would indicate proper alinement. As you would stroke the tone would very indicating a good or bad stroke by reacquiring and or losing lock tone. This type of technology exists and a simple no english trainer program could be made to simply help beginners see the shot and have a positive tone response as they stroke the cue. An instructor could help with the details in hands and feet position while seeing and hearing threw a sister device.
So Scott Lee when do you want to start funding development?