I made an update post about 2 months ago adding a couple new rules in order to avoid the contest getting abused. The rule of needing 25-50 SP (depending on the market price) to participate was added and actually worked out very good so far I would say.

The first full season running this contest has been a bit of a search with many tweaks to get to a format that works. The idea is to have a weekly contest that is fun and profitable to play for contestants and supports members who want to grow on this platform in a way that is fair, easy to host and highly resistant to abuse.

• Increased Guaranteed Prize Pool if 50%+ of payouts are powered up.
  I have been thinking about ways to encourage contestants to power up their winnings as it helps create a habbit to grow which also helps Steemit as a platform. This made me come up with the idea to increase to guaranteed weekly prize pool in case at least half of the winnings were used to power up. Right now the guaranteed minimum weekly prize pool is around 5$ which will double to 10$ if more than half of payouts (usually send on monday) are manually powered up by the time the next contest is posted (usually on wednesday). 100% of the post SBD will keep going to the jackpot.

• Only contestants who build the Jackpot can fully win it if it's not unlocked after 4 weeks.
  I want to avoid snipers to run away with the prize pool in case the jackpot grows too big which is the reason I'm adding this rule. If you entered at least two times during the first 4 weeks after a jackpot reset and you win in week 5 or later nothing changes. If not and you unlock the jackpot, 60% will be spit between all contestants based on made profit and 40% will be split between evenly between all contestants who also entered at least 4 times since the start of that jackpot. (I might still tweak this payout system)