Overwattage bulbs for any 9000 series with a plastic base are a bad idea. It's a surprise Hella makes them.
If you want stock lights that blow HID out of the water, you might look into
HIR (Halogen Infrared Reflecting) bulbs. They were a pretty new thing a few years ago when GE/Toshiba made them, and seemed like a gimmick, but they are the real deal. 90% the performance of HID without the issues, and a nice price to boot. Of course, the price has skyrocketed over what they were (used to be able to buy them for a few bucks at a John Deere dealer), and they are getting hard to find as the supply dwindles..but they are still worth it.
Original HIR info thread with part #'s:
http://www.explorerforum.com/forums/showthread.php?t=173793
Newer thread about Philips HIR bulbs:
http://www.explorerforum.com/forums/showthread.php?t=296573
Other than that, your best bet is "plus" halogens like Sylvania XtraVisions, Philips Hi-Visibility, and Philips Vision Plus. These are available at auto parts stores and even Wal-mart/K-mart, so an easy upgrade over regular bulbs at a decent price. But the HIR is what you want for ultimate performance. Keep the regular bulbs as a backup either way.