You've hit on exactly the issues I encountered with hand-coating the aluminum. It's basically impossible to lay down a flawless coat. I eventually decided it wasn't worth my time and switched to using beautifully pre-coated sheets manufactured in a controlled environment.
www . horizonsisg . com/ sells a sample pack of their product in the 8.5x11". Order it, give it a try, and you'll never go back to hand coating again Smiley