hi cupoftea, going the stencil route is also a good idea. I did this on my panther as it is easier to "distress" stencil applied airbrushed markings than decals.
If you notice in your pictures, the decals applied look too "neat" compared to the rest of the tank which you already weathered. If you had airbrushed the markings using stencils, you can vary the intensity of the airbrush or even cover some areas so that the markings themselves look faded or chipped.
Here is how I applied the unit markings on my panther. Please follow the latter posts for details.
viewtopic.php?f=22&t=8956&start=340
One note of caution when airbrushing marking using the stencils is to cover as much area of the tank you do not want painted to prevent overspray as they cannot be fixed without repainting your base paint.
I bought the stencils here
http://www.rctank.de/TIGER-I_6. They have a lot for the Tiger 1.
Hope it helps.