Thanks for working on this! Looks pretty good to me.
Would you consider using the light:*=* namespace? These are in use, though much less so than the older and in my opinion inferior lamp_*=*-style tags.
For example:
light_source = lantern
light:method = led / high_pressure_sodium / metal-halide
light:mount = bent_mast / straight_mast
light:support = pole
light:height = *