I had a little epiphany this morning while I was running. And this may seem completely obvious, but it occurred to me that there is absolutely no formula for good art. You can follow every rule of thumb you've ever heard, but you are still not guaranteed a good painting.
I did a few larger paintings a number of months ago, and this is one of them. It is 12x12 inches. It seems positively huge compared to a 6x6, yet still a comfortable size.