I don't think the 9007 will fit. Wattage-wise, a 10-watt bump is nothing to worry about. It's the 90-100 watt bulbs that will smoke the wiring and melt the plastic lenses.

I've had good luck with the Sylvania "Xtra Vision" bulbs - NOT their newest, market-hyped Xenon wannabe, or the blue tinted bulbs. Short of getting the pricey Euro headlights, the best you can do is to make sure the headlights are getting full battery voltage. Take a voltage measurement with the lights on right at the bulb or as close as you can, and compare it to battery voltage. If you're only dropping a quarter of a volt, that's about as good as it gets. If you're losing a half volt or more, then it's time to go to relays and/or heavier wire.

Looks up Daniel Stern's various lighting articles on the web - excellent info.