I assume you went through the focusing procedure I posted here. viewtopic.php?f=7&t=287
Your second pic engraving looks OK, but it does look like the laser's burn lines may be overlapping instead of laying down next to each other and causing a slight blur. You may need to secure the lens with a few dabs of hot melt glue between the lens thread and the heat sink/laser module too.
Also we sand the wood across the grains with fine sandpaper before lasering the Image. Have you tried using varible laser power with a color or grayscale image instead of pulsing the laser on/off with a 1bit Dithered image?
If you prefer using a Dithered image, don't use the Gray Scale Curve in PEP6 as it will add grays back into it and the gcode will not have just two power levels.