I've decided to browse through some of the phpMyAdmin code in order to get more familiar with it.
So I started my day by looking through all the include files of server_status.php (finding all kinds of curiosities like /* We must do hard way... but almost no chance to execute this */) and somehow ended up with recoding the chart classes to make them use theme-specific colors, since I found those green colors awfully unfitting from the day I saw them. Also, when I'm going to rebuild the Status page, I don't want to have green graphs there ;)
So this is the result in the themes original and pmahomme (before/after pics):
Since there was such a nice 'layout.inc.php' in each theme folder defining some colors, I thought it'd be best place to put the color definitions.
I will be posting the patch to the mailing list and push the changes to my repos once I figured out how it works :|