In fact, I'm actually going to re-do this completely. The finish to the foil is fine, but I'm not happy with the extra bumps underneath. Plus, I failed to measure the length correctly, meaning I have a half width tin sheet at one end - not very prototypical.
However, the points above, plus the knowledge that the plasticard will bend and stay bent means I can do away with the laminated card and just use plastic for the frame & shell, then add the foil, using thin pva, and it should look much better.
I might even add a window.