Bulbs (especially the incandescent type) do get dimmer as they age. If you're simply trying to increase the brightness because the old bulbs have aged, I'd look into replacing those before shelling out a couple hundred bucks just to keep up with the Jones's.
The Key Differences Between LED and HID:
HID headlights are the brightest on the market, and the light they emit covers a larger area than halogen and LED bulbs. In fact, the area covered by HID headlights is nearly an entire third larger than the area covered by LED headlights. HIDs are also more effective at lighting up the sides of the road.