Also, Deb commented to me that showing "all bets profit" as -20 looks bad and will be off-putting to gamblers.
Better, she says, to show "site profit: 20".
I don't know if she's right, but she's usually pretty intuitive about such stuff.
Agreed. Telling gamblers others have lost X amount of bitcoins doesn't really encourage to play

But, what happens when gamblers start winning ? The Site Profit will show in -ve and investors will be discouraged !!! It can be kept in a logic I guess...
When Gamblers are winning => Bet Profit
When Gamblers are losing => Site Profit