Love the 3-2-1 point format, you would see a lot more teams (especially those chasing in the standings) going for it in the third period of tied games, as opposed to sitting back and playing for the extra point (the Kings being one of the most guilty teams in the league at this). It would incentivize winning in regulation.
But you would have less parity, and the league and it's owners LOVE parity and so many teams getting the loser point in 3 point games. There are a lot of sucker fans (such as one who posts here) who love to talk about their "95-100 point team", while being completely oblivious that half the league reaches that threshold.
People think their team that is 30-30-9 is a ".500 team" the same way that a 30-30 NBA or MLB team is .500, just not realizing at all that those lost 9 points are going to competitors.