Ike,
Some more reading for you. Within the basketball sabremetrics community, there has been a lot of talk and research on the topic of efficiency. Shot location plays into this largely. Take a look at the following chart:
http://hoopdata.com/teamshotlocs.aspx
Notice that instead of three point percentage, they use a metric called "Effective Field Goal Percentage" or eFG%. This metric takes into account that three pointers are worth more than 2 points, and the shots are weighted accordingly. From this table you see that the most valuable shot in the NBA is still the dunk/layup with an expected value of 1.26 points this season. The three pointer is next with an EV of 1.01, with everything between being around 0.75.
This just scratches the surface of the analysis, but I figured it would give you a good taste of what's being studied, and some insights into effective NBA shot selection. I'm sure you'll find a lot more interesting questions and answers as you dig deeper.