How do I change my competitors for scenes?

The competitors on your scene leaderboard consist of club teammates, FB friends, and a small group of boat friends that Wooga gave you for exchanging bushes. You can try asking customer support to see if they can change your boat friends, but the remaining competitors will still be there and being top of the leaderboard has no game advantage.

I have a similar problem - one super high scoring player who dominates every scene. I contacted customer support and the response was that the default group of friends on your boat can't be manually changed. Players who are deemed "inactive" are removed from the boat list by the computer and replaced, but if you are connected to Facebook those friends would not be replaced. Then I asked what is the period of time to be considered "inactive" and if I stopped playing for that amount of time would I get a new list of friends. The response was that an "inquiry about a specific time frame falls outside our scope of support."