Well, for one thing, "lines" are generally kind of vague ways of determining focal point or motion. Your tree branches here, are "lines" pointing into the picture, and leading the eye towards other things. The one on the left seems to be pointing to the other one, which in turn is pointing mostly up and out, if that makes any sense...The grain in your ground texture seems to be pointing towards the right and into the distance, and the cloud "lines" are pointing towards the sun. This is actually pretty good as far as simple pics go. As for "balance", there's all kinds of balance: color balance, object balance, mood balance... Balance is a form of "tension and release" (a term occasionally used in music composition). "Balance" is really kind of subjective, but it's fairly simple: If it looks balanced, it generally is. This picture, to me, seems a little "right-heavy" in the balance, what with the "weight" of the trees and the sun both mostly to the right.