1. Bitcoin isn't practical for micro-transaction, decent percentage of BTC could loss to withdraw fee (even if it's 1 sat/vbyte).
I realize this. And of course, the problem would be accentuated by the fact that payouts to players would be very small to begin with. Could an alternative be to payout using an altcoin? Or, possibly, set the minimum threshold for payouts high enough that the fee would become less of a problem. That way, only players with sufficient balance would be able to withdraw their earnings. It might be possible this threshold is set unreasonably high for a single player to achieve, thus requiring a team effort or guild structure.
IMO using altcoin (such as Doge) is more practical. There are times when Bitcoin mempool is full which makes transaction fee very expensive.
Few concern/problem,
2. Moderating the community who have financial motivation rather than having fun (for example, compare this forum with other forum which discuss video game/movie).
I'm sorry, I don't understand. Do you mean it might be a problem if players join out of financial motivation rather than having fun?
What i mean is player who join out of financial motivation is likely to be less friendly and use deceptive tactic to earn money.
In-game advertising is technically against the EULA.
Thanks for the info, EULA, ToS, etc. sometimes are difficult to understand.