An LED bulb in the existing housing is not a good idea. The pattern of the light produced by the LED bulbs is radically different than that of the halogen bulbs, and this throws the overall focus and pattern of the headlight all out, quite possibly making it more blinding to other drivers and/or illuminating the road directly in front of (and close to) the motorhome excessively, which is counterproductive even though it makes the lights look really bright. The same general thing applies to aftermarket HID bulb kits, too.
The simplest reasonable upgrade is brighter halogen bulbs, but they're somewhat limited in what they can do and to burn more brightly their lifespan is reduced by a considerable amount. If you don't do much night driving, that may still be a reasonable tradeoff.