I would highly recommend using a viewport in your UI since you have a section of it clearly blocked off there is no point in having the WorldFrame render behind it. For instance if you had nameplates turned on and a nameplate was behind your action bar, you couldn't click on it anyway cause the UI element of your action bar covers it up. You can use a viewport addon to adjust your WorldFrame so it does not render behind your UI elements.
"In anything, if you want to go from just a beginner to a pro, you need a montage." /w TankSpot WTB Montage for Raiders.