Adjusting active/passive window contrast in Aero

With Vista Aero, I have trouble seeing the difference between the active and
non-active windows. In the title bar, there is a slight difference in
darkness, but not very visible.

How can I enhance this difference in Aero? I know that I can get a high
visibility difference by reverting to Windows Classical view, but I want to
stay with Aero, just making some costum adjustments.

I also know how to change the colours in Aero. But regardless of colour
choice the problem remains: That the difference between active and non-active
windows is not very pronounced.

In Windows Classical view, I was used to adjust all these things easily. But
with Aero, the scope for costum adjustment has been narrowed down a great
deal. That is really a shame. If you can tell me some way to get more control
of the appearance, I would appreciate it.