True there is sight, and I won't deny your points on that, but I was talking about a more physical representation of them. Like...Luxray has a form of x-ray, but IS it an x-ray in some way, shape, or form? Luxray, being an Electric type, is more of a vector or a harnesser of light. Light types would be closer to a manifestation. I'm not sure if that makes sense but I hope so!
Once again, I would like to say that Light types would likely not represent angelic beings! After all that is pretty much the Togepi line, as you said. I do suppose a pure Flying type, which we've only seen one of, might be a good candidate for the closet thing to a Light type, though honestly I think pure Flyings will just end up as windy things. The only Normal/Flyings we've seen are quite ordinary birds, and I think it might be a bit disappointing to have some sort of abstract, Light-like being technically be in the same category as them. If it were single Normals, then sure, but the dual types are more of specializations.
Fighting is a "hero" type, not a "spiritual"/"spectrum" type. If they're based off of the Japanese idea of heroes then I think a Fighting/Flying type is more likely to be a sort of Garuda, not an angel, as you term it. So far they've all fit into a very physical appearance mold, disregarding the muskedeer.
Your last point is really valid...Though I'm operating by the assumption that their type meaning in and of itself is not angelic. So Arceus would be good as a Normal type, as it is the originator of the universe and everything in it, with Normal being like the average of all of those types. Light types would just be a more specialized, narrower range of qualities like Fighting or Psychic or Flying is.