Match-Player Ratings

Instead of just awarding IP Points, increasing levels, and having basic game and historical stats (k/d/a), I think it would also be beneficial to add a match rating. Whether you'd want to have a cumulative player rating that averages these match ratings by role/champion/game/etc. is subject to debate (also if you want to make these public information or have a setting to allow players to make them public if they choose). I don't have a definitive formula for such a rating, but perhaps it could be something like:

Rating = (Kills per minute + 0.5[Assists per minute] - Deaths per minute)*100 (+10% for the win)

I'm not sure if it would be beneficial to include minion kills, tower/inhibitor destruction, etc. to establish lane stability for 5v5, but this may be a bit unfair since the roles can vary quite a bit regarding these accomplishments. Perhaps the above can be a "Champion Combat Rating" and you can also include a "Gameplay Rating" that will take these other factors into account.

Again, to make these ratings public, could cause some movement away from support or jungle roles since you can't necessarily award points to the vital, but difficult to standardize (such as teamwork or sacrifice), actions of these roles. Users could also take advantage and potentially set up a game in which the other team purposely feeds so one user on the other team can gain the "high score" with an unseemly amount of kills. Although for this to happen, a player needs to sacrifice their own rating... but people can probably build bots under a masked user. Who knows... people can be extreme.

The question may be, are the levels, honors, and standard k/d/a enough to satisfy the average user? I would, personally, like something a bit more than this for games outside of the ranked world, if just for the ease of asking a friend, who allegedly had an "epic" game, "what was your k/d/a and did you win?", you could ask, "what was you CCR (Champ Combat Rating)" or GPR (Game Play Rating)?

Obviously, you could take this pretty far and make the formula(s) extremely complex, then again, what you currently have is very simple, and maybe that is enough for the average user. I will leave that to you geniuses out there on the message boards and at Riot who have far more experience and knowledge than I.