I typically do a light layer of clear for the decals and finish with a few heavier coats after they've set. That way you can sand/buff the clear coat over the decals for a smooth finish.
I'm new to the board, and also have this kit next in line. I love your concept of the Umbrella Corp! I'll be building mine pretty basic out of the box for my Lieutenant. It's my first helo build. :D I'm looking forward to seeing this!