MoneyPot aka its investors accept bets according to the kelly criterion, so by minimizing the house edge (minimizing the investors' odds) you're minimizing the amount of the bankroll that the investors are willing to stake. Obviously, with every bet, the investors are staking wager*multiplier while the player is staking only the wager.

In other words, if you minimize the house edge, then you're guaranteeing that nobody will ever be able to make bets with large wagers or high multipliers because you're directly limiting the max profit per bet.

So the "minimum house edge" is the one that lets your players make the bets that they want to make. This includes whales and, for example, players that don't want their bet to be rejected when they're trying to double their wager on their 5th consecutive martingale loss.

I hope that illuminates why there's no real answer to your question. Players want a low house edge, but they also need a house edge high enough to attract a counterparty to their bets (the investors).

You can get an idea of how house edge impacts max profit by playing with the "Payout Editor" I made on plinkopot.com.

http://i.imgur.com/hSUoibY.png