2) On the bigger exercises, always do warm-up/ramping sets, to prepare your body for the coming strain. (I need to work on this myself.)
3) Hold back a little on your right, if you'd like, and work harder on your left. That makes sense to me. But, again, not a certified health professional. I'd also recommend something outside of weight training, like Yoga. For some reason, I can see this strengthening and enhancing balance to the muscles, since it's very much a part of the practice to do the same thing on both sides. But, utilizing an extra workout activity is entirely up to you. I think that your left side will eventually meet your right, as long as you remain consistent.