Ask HN: Need rules suggestions for my multi-player snake game

So I'm building a multi-player snake game with HTML canvas, MooTools, node.js, and socket.io as a learning experience. I just completed what I thought was the hard part, which was making the bare bones of the game like having 2 snakes in an arena, making a snack/score system, and most importantly having the two browsers be perfectly in sync with each other while updating 15 times a second (spend all day removing lag from responsiveness and synchronization).

I just realized that I completely suck at making rules for a compelling game. The rules in the game as of right now are simple but flawed. You get 100 points for each snack eaten and you win whenever your opponent dies. You get a bonus if you kill your opponent, which means they crash into you and not the wall. The flaw in this is, you getting a high score is entirely dependent on your opponent not sucking and not crashing into walls and such, because when that happens, the game is over and you can't score any more. I definitely want a leaderboard so this can be frustrating to good players. So I guess I'm just wondering, what kind of multi-player snake game would be the most fun for you? Would you want more than two snakes per arena? What kind of bonus should you get for killing other snakes? Should you win via a point system from eating snacks or how many times you kill your opponent?

Here was my main thought process when starting this project: 1) You grow your snake by eating snacks like a traditional snake game 2) The longer you grow, the easier it is to trap your opponent

However I'm having a tough time assembling these ideas into rules for a full game. Any ideas or help would be very appreciated!