I also modified the rw/play/stop/ff buttons to have softer grey borders. I'm not completely happy with it (they get "lost" among the grey background) but I like it better than the dark harsher borders. The 134,134,134 value is taken directly from a colour picking tool over iTunes in mini-player mode:
updated:
<!-- 86--> <element id="Player.Control.Default" bg="242,243,245" bg2="182,183,185" fg="81,81,81" bdr="134,134,134"/>
<!-- 98--> <element id="MiniPlayer.Background" bg="230,230,230" bg2="147,147,147" fg="95,95,95" bdr="198,198,198" />