Frank,
What monitors are you using? I'm only listening on the Macbook at the moment, but your first mp3 has a nice dry sound. A little honk, maybe, but as someone mentioned that's how those guitars sound.
Get someone else to play it while you stand in front of your own guitar and see what that sounds like. Be prepared to be surprised. While you're there, stick a finger in one ear and, at about 2-3 feet out, move your head around listening with the other ear. Acoustic guitars project lobes of sound from different parts of the face. See if you can find one of those lobes that you like and put your mics there.
I do like the second pair of strings better.
The D50: You're throwing $500 at the project for mics and recorder. The mics I use cost almost $2k today. They were a lot cheaper when I bought 'em.
The good news is you are starting to hear the difference that gear can make. The bad news is that you're starting to hear the difference good gear can make.
Nice playing and please don't beat yourself up.
Regards,
Ty Ford