Submissive Contest

[Ranai]

For inspiration (and lots of fun) I can recommend reading 'Monica's Games' by Richard Alexander, Book 4 of the Monica series. The second part of the story is one long contest between two teams. Swimming, running, weightlifting, fencing, cycling, pony play, walking, quiz, paintball, treasure hunt, assault course. The arrangements in the story are often technically elaborate, but I think various ideas might be picked up and simplified for DIY purposes.
The actual games take place in chapters 17-30.

With a lighthearted approach, it sounds like fun. Personally I'd see no great emotional pitfalls in a contest, as long as everyone involved knows that it's just a game, just as a board game or or a friendly sports match, and nobody is really being 'compared' to anyone.

Suggestion for reward/punishment:
The loser gets tied up in the position she dislikes most. With any extra discomfort factors your devious Doms wish to add. She gets decorated with chocolate body paint. The winner may lick it all off. She may do this at her own leisure, thus determining for how long the loser has to endure in this position. Maybe everyone else will have dinner together first, while the loser AKA the dessert awaits her turn tied up close by with an empty stomach...