Extended gameplay ideas
Seasonal play - optional wipe of player's stats every ~2 months, can be disabled in settings, some kind of color or icon reward for top players at end of season.
Tournament mode - starts when 16 players sign up, 2 tables of 8 start, winners play a 2nd game, winners of that gets some sort of icon/color reward
I like both but seasonal > tournament.
I like both but tournament > seasonal.
Do something else.