Please add statistics for multiplayer, i.e., how the statistics for player's money earned, shots taken, beers drank, is shown in single player. This would promote a very competitive environment and would give players a reason to keep coming back.
Simplicity is very important but I would like an incentive to kill other players more often than not. Most players tend to even out the health between everybody at the table to keep the odds of them being shot lower due to everyone else having more people to shoot. I would like to propose adding a slight advantage of some sort to a player for getting a kill. For example, hypothetically, if you kill someone in round 1, in round 2 you get a starting item of your choice. Furthermore, if you get a kill in round 2, it will stack with your kill in round 1 allowing for a slightly larger advantage in round 3.
Money. Let us use our money that we win for something, anything. It can be very simple, (new masks to wear for example). Just give us more reasons to come back to this game.
Concealer. A new item that allows the user to hide their portion of their table until the shotgun gets loaded with new shells.