The leaderboard is promoting spam, it encourages about the same half dozen to create a thread each day.
Giveaways and competitions based on talent is by far the best way to reward content, that is already done now and I’d like the leaderboard prizes to be given instead in competitions.
That way all content is what people actually want.
I also don’t recommend purely on points system as that encourages just multiple accounts to increase chances. An individual can if they so choose have multiple accounts each accruing points to then each bid to win.
Talent based rewards is the way to go as you can’t win particular through brute force multiple accounts so much while at the same time all content is relevant.
So keep the photo competition, etc, but make the winner get a prize rather than points to use which then has to compete with multiple accounts.
Once it’s setup to be fair and fun then leave alone. I’m only mentioning it as it isn’t now.