I think you should not make the coin completely free of charge. Or leave the limit on the number of users when the fee is not charged. It's good marketing) In the end, you should receive money for their work. It is better to pay for stable performance of the pool than to after some time problems due to the fact that the owner would be that interested
I will charge a very low fee then, but this is not the idea of the pool, I will prefer a donation system, but users "must play the game correctly" :/
There is some donors, but not much to handle electricity cost
