Not much on Sheldon's site???
Did you look at the gear calculator?
http://sheldonbrown.com/gears/
Plug in you existing set up and print/save it.
Analyze it. What ranges do you use.
Are there any gaps you would like to fill. For example if you use 15 & 17 a lot, would a 16 be useful etc.?
Any gears you don't use etc. What do you give up?
Plug in the new combination.
Compare the Gear Inches.
Is it an improvement.
What do you give up?
I don't know what will work best for you. Maybe the 12-xx or even an 11-xx???
You didn't mention the number of cogs on the back, so your mileage may....