Originally Posted by
time0ut
Yes, if you are a healer, your raid frame will take up a good bit of your UI. It shouldn't affect your raid awareness though. Just keep the central area around your character clear of stuff and you should be fine. For example, I keep about a 4x6 inch area clear in the center of my screen with my unit frames on the left, target unit frames on the right, and raid unit frames underneath. This works well for me because my eyes are always close to the center of my screen.
You mention not needing mouse only healing options. I also do not care for mouse only, but all of my healing spells are mouse over. Its very important that you do not need to target a player to heal them. Having to switch targets for each heal can severely limit your throughput.