Yeah, i would definitely take another couple cracks at that guitar part. You're almost there. With some more practice and maybe the use of a metronome, you should be able to nail it.
Do you have a second mic you can use? Since it's just vox and guitar, I think you'll get a much fuller sound by recording the guitar in stereo. Alternatively, if you don't have another mic, consider practicing a whole bunch until you can play the part consistently. Then double up the track panning one hard right, and the other hard left. just a thought...
Also, consider bringing the mic in closer to the guitar (more like 1 foot away rather than 3-4 feet), and also playing around with where and what direction in the room you record.