A pair of AKG 414BULS. About 6-8" off the guitar. One aimed at the 12th fret. One off axis aimed at a point above the sound hole and toward the bridge saddle. Cardioid pattern.
An Oktava ML52 through a Drawmer 1969, aimed at a point above the sound hole and toward the bridge saddle.
I double track acoustic a lot. Neil Young's After the Gold Rush has some good examples of double-tracked non-identical performances on acoustic.
The best acoustic sound I ever got was my Taylor 710 into an AKG Solidtube through a Drawmer 1969. I was wearing headphones and adjusted the guitar instead of adjusting the mic until I heard something I liked through the phones. I was pretty close, the guitar was within about 3" of the mic. Pretty weird, as the Solidtube wouldn't have been my first choice. It was up as I was doing vox.
Another thing I've found to amaze is an AKG C1000S through a Langevein DVC.
For singer/songwriter types tracking all at once, I like a pair of figure 8 patterns set up to reject the voice and guitar. Usually use a pair of 414BULS, but have used a pair of Oktava ML 52.