I don't know exactly what Hazel's tasks will look like, but I would prefer the limit of 9 pixel tasks, as there could be tasks that give 1 to 10 pixels (and you could control this variance by stipulating a median so that no one has a value less than X or greater than Y total pixels added per day/week/month, depending on the time you want to control). So that tasks that pay more pixels could request higher level items and the median values ​​would adjust according to the level/reputation/VIP/land owner/etc that you stipulate.
So players would be divided into Tiers, for example:
Tier S: land owner + vip + reputation 6000+, wtv..
Tier A: exemplary players.
Tier B: average players.
Tier C: players who only have 1 or 2 skills with high levels. (account farmers)
Tier D: new players
And each Tier would have its own median, allowing Tier S players to receive more pixels over the time stipulated for the median than players in lower Tiers.