nyan!
Uhm just to start of somehow - im Level 15 (1/2) and Gold 4.
I only play with a full Squad where everyone is between G5 and G1. After the first 10 Matches i got ranked in in G5 after a day playing only MM i finally came in G4 and theres the Problem - after i got upranked i simply couldnt anymore.
My Friends jumped from G5 up to G1 and le Kitten (aka me) is still in G4… Weve played about 60 to 70 Matches in one week (im always between the first place and the third one) and mostly won them (max. 2/10 are loses).
Im main (Ninja-)Engineer (proxy, fletcher, bush) - ive mostly repaired the ev before the first push is even over (25sec on bridge), planted the c4 before the enemy is even able to kill one of my team or took the emp/drug thingy before the enemy is able to rotate back 
Sure i die mostly after i finished the obj and dont have that many kills (sometimes im extremly negativ) but im always in the higher places of my team… (7:40 once 
)
Slowly im getting mad, i really want to have a higher Rank but i dont think its possible with my play style 
And yes, ive tried to play other classes like Support or Medic but i simply cant play them, theyre to slow, to passive theyre just useless for me 
How does the Ranking System in MM even work ?
Hulp
Kitty
PS: Sry for my lack of English skills today - my brain is all messed up atm - pls dont hurt me - except u want to ;3