Are they hazed and all yellowed up? If so, either take some Mother's Aluminum Mag and Wheel cleaner and rub it on there and wipe it off, or get some really fine like 400 grit sand paper and wet sand them, then finish off with some Mother's plastic polish...
If they just aren't bright enough, well, you can always get some $350 HID bulbs for them off ebay...
ya I had a hid kit in my car for a while, really bright and shine a little farther. But if you really want to see far, do a projector retrofit. I've got regular bulbs back in mine now and hate it, can't see for crap
Mustang lights have never been very good, the brights just suck... My 86, 99, 2002, and now my 03 cobra have all had crappy lights... high beams on my 02 explorer just rock... light up the sides of the road and trees very well...
Yeah I'll agree that the headlights on these cars aren't exactly great when you're at speed, it's easy to "outrun" the lights.
When looking at your headlights are they "hazy" on the outside or inside of the lens?
Have you tried upgrading to a different bulb (not one that is significantly higher in wattage though, they could melt the wiring! LOL). I swapped in a set of Sylvania Silverstars bulbs (same wattage as factory bulbs) and noticed an improvement at night. They produce a "white" light and are an excellent upgrade if you don't want to spend the huge $$$ on a HID/Xenon kit.
Here is a link: http://www.sylvania.com/auto/silverstar.htm
Now, if the exterior or interior of your headlight lenses are "cloudy" or "hazy," and if the 94-98 headlights are similar to the 99+ design, maybe you could try cleaning them up yourself? Here is a good "how-to" article from fnsweet.com, which shows how to convert to "clear lenses" but allows you the chance to clean up the lenses while everything is apart:
All I did to correct my seeing problem is angled my lights up. That way people always think my high beams are on even w/ they're not. Never been pulled over by the cops either and I've been behind them at night. I've had a few people tell me to turn off my beams though. All I do is flash 'em my brights, laugh and leave.