If you've driven a car with HIDs in projectors, you'll notice that the intensity isn't the only improvement - the beam is much wider, and goes much further.
That's really a feature of any projector headlight unit... I've got a set of OEM halogen projector fog lights on my car, which have that wide, flat beam pattern you're describing. Similarly, my mom's '05 Subaru Outback has halogen projector low beams that also provide that wide beam with a sharp cutoff line.
The distance the headlights throw light is a product of the reflector/projector assembly's light intensity pattern and the total amount of light emitted by the source.
In a projector assembly, you want the light pattern to be brightest right at the edge of the cutoff line, with a exponential decrease in intensity as you angle downwards. This is because the edge of the cutoff will be the furthest point from the vehicle that the headlights will be able to illuminate, and therefor will need the greatest portion of the available light to reach and illuminate properly. As you angle downward, the headlight will be lighting areas closer and closer to the vehicle, so the beam pattern should get progressively weaker.
This is actually an issue my fog lights suffer from - the designers made the beam pattern emit an almost perfectly even flood of light, constant in intensity right up to the cutoff shield. In use, that means the area immediately in front and to the sides of the car is brightly illuminated, with very little light thrown down the road.
Anyway, back to the other half of my product statement, the emitter. HIDs obviously have an advantage in raw lumens, but unfortunately can't be simply swapped in place of halogen bulbs. The problem arises thanks to the shape and intensity pattern of the light emitter.
A halogen bulb has an essentially cylindrical light emitter - a coiled, and re-coiled length of tungsten wire. The wire is constant in diameter over it's length, so glows at a very even intensity over the entirety of the emitter.
An HID bulb on the other hand, has an oval-shaped light emitter. Light is generated when high voltage is passed through a capsule of gas via electrodes at each end of the capsule. The interior of the capsule is larger than the electrodes, so the current flow that forms the arc can (and does) spread out once it has left the electrodes, yielding the oval shape. Further, this spreading of the current causes a significant variation in light intensity across the arc. The arc is brightest at the ends of the oval where the current flow is greatest (around the contacts) and dimmer in the middle where the arc spreads out.
These differences are a problem due to the way reflector headlight beam patterns are commonly composed - by layering up multiple "images" of the filament. A beam pattern that is sharp and well controlled with a halogen filament's even rectangular profile can be come blurred and scattered with the varied, oval profile of an HID retrofit.
I probably could use some upgrade myself!
I probably should spend some $ on a new car vs. collecting some more lights! 
