Mastery Rating For Junglers is Broken

The current rating system for junglers highly favors high farm values over other statistics such as kill participation, KDA, vision control etc. and also doesn't take into consideration the build of the player. A tank Udyr (using this as an example, not 100% accurate) is less likely to splitpush/take minions from laners in comparison to a full damage Udyr who would avoid team fighting and attempt to get as much gold as possible in order to afford the damage items he needs. Also damage items are generally more expensive than tank items so therefore the damage Udyr will need way more gold to reach 6 items compared to the tank Udyr, resulting in the tank Udyr not caring for farm as much sooner and he is more likely to get gold from kill/assists from team fights, therefore acquiring less CS.

I just won a ranked game as Skarner and went 12/1/13 in Diamond ELO, having the highest amount of kills and kill participation, least deaths, and 2nd most assists in the ENTIRE GAME only to receive an S- however i was 3rd from last to farm as after the 25-30 min mark I didn't need to farm as I was pretty fed and didn't need anymore gold, so I left side lane waves and jungle monsters for my laners so they could reach 6 items sooner and be more of a threat. Currently there is 2 ways to play Skarner and that is tank and damage heavy but the Mastery Rating system is also comparing me to the heavy damage Skarners even though they have completely different play styles and could very well be classified as 2 different champions. I'm a Skarner main and ever since level 6-7 mastery levels have been introduced its been insanely hard for me to even get an S as the system takes CS into a huge factor as I could end the game 7/3/15 and only get an A-. Even on other junglers who really only have a static build such as Gragas i find pretty difficult to get a S on because it seems like i need to tax a lane every 2 minutes just to get an S and showing up and taking laner's farm without reason isn't a true sign of "Mastering a champion" that's just being greedy.

Also Im not sure if the rating system takes damage dealt to champions into consideration but a tank Skarner should deal less damage than a Skarner who builds damage which in turn could also effect how rating on a champion could be calculated.

Here is the Skarner game: http://imgur.com/DgLEbxI

Here is the damage dealt to champions graph: http://imgur.com/IHWCINU

TL;DR: Junglers are graded too heavily on CS and the grading scale doesn't take into consideration if they are playing a damage heavy or tank heavy play style/build on a particular champion, therefore changing their need for gold and what the endgame damage dealt to champion stat may be.