I understand ice has a lot of weaknesses, but it just would not make sense for light to not be super effective. In general, light does a better job melting ice than fire. I also did not want to miss with any canon type matchups. Not every type can be perfectly balanced. I get that this is particularly tough for Water-Ice pokemon, which makes a lot of them really bad. But there are plenty of otherwise good pokemon that are ruined by 4x weaknesses like Moltres, Charizard, etc. In the end I went more with what made sense for the type vs too much balancing. There aren't that many light type moves and Pokemon in the end, and not many NPCs have Light types, (SPOILER ALERT: besides the first champion) so hopefully it doesn't break too much if you wanted to use Ice type Pokemon.