I'm not a huge fan of Light type as I don't think it's necessary. Solar Beam works under Grass, Sunny Day is fine as Fire and any 'Holy' attacks would probably fall under the realm of Ghost, as counter-intuitive as it sounds. Unless a particular religion is intended to be invoked, which I would personally think unadvisable, those sorts of attacks fall under 'supernatural', and thus Ghost. Or Fire. Or Water, if you really want a 'holy water' attack.
Sound I don't think is necessary either. Certainly there are a variety of sound-related pokemon, moves and abilities, but I don't see a need for it as a type. Normal covers it pretty well. Retroactively typing all those to 'Sound' would complicate matters and not really fill any gaps. I think that the distinction between 'ground' and 'steel' was significant enough to introduce that divide, and certainly in oriental philosophy. Dark I think was a wonderful introduction, and I love it to bits.
If I was going to introduce a new type, it would probably be 'Cyclopean', for all you Lovecraftian folks out there. You've gotta love Cyclopean. And no, not just for pokemon with one eye...
Sound I don't think is necessary either. Certainly there are a variety of sound-related pokemon, moves and abilities, but I don't see a need for it as a type. Normal covers it pretty well. Retroactively typing all those to 'Sound' would complicate matters and not really fill any gaps. I think that the distinction between 'ground' and 'steel' was significant enough to introduce that divide, and certainly in oriental philosophy. Dark I think was a wonderful introduction, and I love it to bits.
If I was going to introduce a new type, it would probably be 'Cyclopean', for all you Lovecraftian folks out there. You've gotta love Cyclopean. And no, not just for pokemon with one eye...