BIG BAD WOLF: There does appear to be a correlation between average games completed and average ratings. I compiled these for the top 50 players in each variant. Here are the results (Variant/average rating/average completed games):

Crowded-1870-169
Nack-1901-195
Race-
1912-201
Hyper-2145-801
Back-2219-792

Note that, with the exception of Backgammon, the averages in both categories are in rank order.

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