I kept the stock wattage h4 bulbs, and later upgraded them to the Hella h4 plus bulbs - same wattage, but just a bit of Xenon gas and they are claimed to be 30% brighter. Philips Premiums h4 also do the same thing. I got the Hella h4 (HL78150 60/55Watt) from Susquehanna MotorSports for $27.36 shipped to my door, and they are indeed somewhat whiter and brighter than the stock h4. If you don't have bulbs already, I would start with these - they are about the same price as standard h4 bulbs. If they don't do it for you, then you can upgrade to something else, but the Euro lights have such an improved pattern that you will probably not want to bother with over wattage bulbs.
By the way, I saw in your post that you are contemplating new springs/shocks. Check out the Sportline package from the PartsShop - I love what it did for the handling and ride while still keeping it all MB parts!!!
87 300E, 65k miles
[This message has been edited by JCE (edited 06-09-2000).]