My First Official Chart

I wanted to put some spaceships on my Alien Illusion Scarf, so my spouse sketched up a little alien craft and I came up with this chart.
It's designed for the 40-stitch scarf width, with the little ships running the length of the scarf (after the Alien pattern ends, that is). The grey squares are optional purl stitches in keeping with the illusion pattern of knit 3 rows, purl 1 row, and kind of look like some weird landscape for the spaceships to fly over.

Well, it's the first chart I've ever posted, so I welcome any feedback. General consensus is that such spaceships were good enough for Atari, so they should work for this, and so far I like them in my scarf.

By the way, I used Excel (of all things) for the graph. You're welcome to use the pattern, just click to make it bigger and print it out. If you have Excel and want a blank chart with the pre-numbered grid on it, just leave me your email and I'll send you one. It was surprisingly easy to do with Excel, since you can both outline and fill in cells with a limited palette of colors. (Photoshop is not my friend, and I spent far more time trying to make my Excel spreadsheets look nice than any sane person should ever admit.) I like Excel. Hence, Excel is my friend.