I'll second the 15 series Martin idea. I have two of them: a 00 and a 12 string J. I've played the 000 slot-head and like it a lot. If I had the money to spare, I'd buy one. But, for an all-round general purpose axe my vote would go to the six-string J-15. I love Martin's J body and could kick myself squarely in the ass for missing a chance to buy a J-40 for $1,200 USD a couple of years ago. If you're not familiar with this body size, don't let the "J for Jumbo" designator fool you. It is not the same size as Gibson or Guild's big jumbos (like the J-200). It's quite a bit smaller. The volume of air in the box is about the same as a dreadnought, but it has a more pronounced waist which makes it a more comfortable guitar to play and makes it much more suitable for finger-picking than a D.

If all of my guitars were stolen tomorrow and I had to go buy just one guitar, the J-15 would be it.

Bruce