Taking into account what you were given and the lack of amplification I think that it sounds great.
Yes, the vocals could be a bit more clear but you would have to get the mics closer to the singer's mouth. I have had some success doing that by running mics instrument height but simply tilting my mics upward a bit toward the vocal source. Not all musicians like a full [secondary] recording rig right in their face.
On the other hand I have used a single stereo mic in an unamplified situation and most musicians are so accustomed to singing into a mic they will often lean forward and sing right into your rig. Alice Gerrard, Tom Sauber & Brad Leftwich in Hocekessin, DE or Highwoods Stringband in Danby, NY are both perfect examples. Unamplified, leaning into the rig, and you can hear every single boot stomp perfectly.