Re: Light strings on an acoustic?
I think Taylor puts mediums on their x10 Dreads and x15 Jumbos and light gauge on everything else. I think Martin does the same. The bigger the top, the heavier the string you should use.
I use D'Addario mediumJ-17 phosphor bronze on most of my Martin Dreads, though I use the D'Addario hybrid Bluegrass gauge J-19 (medium bottom, light top) on two of them--my DC Aura and the MTV-1.
I switched from Elixirs mediums on my Taylor 710CE to D'Addario medium J-17 because the higher tension of the Elixirs made me break strings. No more broken strings since I made the switch.
My cheapie Ibanez Artwood AW50CENT has D'Addario light gauge--partly due to it's lesser construction and partly to have a guitar that is eassier to play when I have a to do a lot of lead work.
For me, the EXP strings are helpful, because they last a long time--good for me as I have so many guitars going through rotation.
Changing string gauges may require adjust met to the saddle height, the truss rod and the nut.
It all depends on your style, hand strength and of course, your ears.
Good luck!
Bill