I always thought with the sheer amount of Vivillon variations there are it was a wasted opportunity to not give them each a unique typing. Each one could have had a different secondary type along side bug (including only bug) and learned a different STAB move at 50 in place of hurricane.

ITT: We give each pattern a typing and move for each Vivillon pattern.

Starting with an easy one

Vivilion: Polar pattern
Typing : Bug/Ice
STAB Move: Blizard