Perhaps in future tournaments, while maintaining the 7-day turn duration, it would make sense to introduce a new rule – something like requiring at least one game per month. Something along those lines. This might help avoid situations in round-robin tournaments where some players have played all 30 games, while others haven't even played half (and are unlikely to).
A more practical approach would be to set checkpoints at 25%, 50%, and 75% of the games. And at each checkpoint, exclude passive/inactive players from the tournament. And, of course, monitor activity in the couple of weeks leading up to the checkpoint and create a list of candidates for elimination.
