Triangle of Ice, Ground, Fire doesn't work well. True, it works 1 way (Ground is great on Fire, Fire is great on Ice, and Ice is great on Ground), however, try the other way:
Fire is normal on Ground
Ground is normal on Ice
Ice is not very good on Fire
The underlined one is an issue, making Ice the worst to choose, in a way. BUT, as it is Lapras, that makes Lapras have the overall advantage, as that is also Water type, so adding that:
Fire is no longer great on Lapras, but normal. Lapras can defeat both Ground and Fire with ease.
So, Lapras is now the greatest. So, you may need to rethink it, if you want fairness.