What you are doing is "pedaling out" You are not doing a ballance wheelie, you are just keeping your front end in the air by pedaling faster and faster. You have to go back a bit more, and try to slow yourself down. And yes using your legs by sticking them out one way or another will help your side to side balance while wheelying.
Hey BIKHawkDown, can you go around corners like the one in your first picture there? I have those priity much perfected now. What is really getting to me though is that I have been starting a wheely completely on the one side of the the road, and by meaning over I can come so close to turning a full 180 degrees and going back the other way (all while staying on the road, about the same size as Hawk's there) and I can never get it. I come soooooooo close I have gotten it to where I have done a full 180, and I my front tire is brought down by me hitting the curb on the other side of the road.