Idea:
How about putting on names of the fastest 21 Zwifters on the turns - it could be with the fastest time every month on turn 1, second fastest on turn 2 etc.
Not that I ever would find my name on one of them - it would take more than a thousand turns 
Kind regards Rune
Or it could be a race where you win your name on the turn. Like in real life. Fausto Coppi first winner in 1952) name on turn 21.
Lots of ways to do it - women and men share a turn.
When the world champion wins with a leg-breaking 13 W/kg attack up the Watopia KOM, and only ends up 8th best time on that climb for the day, it becomes obvious that “fastest Zwifters” doesn’t mean much.
You have a point. There is a lot of cheating going on to make it difficult- but there must be ways around this.