On-line at https://xtecna.github.io/lor-decks-stats/
This site is as simple as it gets. Choose a .CSV file with decks from a tournament, choose the number of decks for each player according to the CSV, set an offset for unwanted data to the left and wait for it to count a tally of regions and champions for all the players at the tournament. I'll try to add some graphs in the near future.
Thank you, AloRenato, for your enourmous help with the reponsiveness and layout! You're the man!