Here are some awesome swimming exercises that can help you chip away at all ranges of your swim system.
Backstroke 3/3/3 Drill: As you swim backstroke over the pool exchange three strokes with the right arm, three with the left and three where you substitute both arms. Keep the non-swimming hand next to you.
Butterfly 4-1 Drill: From a streamline position take four butterfly kicks for each arm pull. Focus on a great streamline position out front with a strong and steady kick. Feel great traction on the water with your hands and accelerate your hands throughout the pull using a high elbow catch position. Breathe on each arm stroke keeping the head in a forward (not up) position (look at the water as much as possible when breathing).
Freestyle Elevator Drill: Start swimming freestyle with your head out of the water in Water Polo position. As you swim across the pool lower your head until it is back in the natural and neutral position. Feel how much easier it is to swim and balance with your head down on the water. Pretend that your face is the bottom of a boat and your nose is the keel. The water will flow across your face as your nose will split the water. If your chin is catching any water then you know that your head position is too high, and you will have to adjust.
Breast stroke Heel Touch Drill: Kick on the surface with your hands at your side near the back of your hips. Raise your heels up and touch your fingers to your heels on each kick. This helps develop a full kick. Make sure you are grabbing water with your feet and accelerate them back to the extended position. As your feet finish in the extended position, your head should drop two to four inches under the water in a slight dolphin motion.