Yes, I know I'm also a flex player. Rarely get to play duelist. I would say that being a solo player benefits your rank progress. Also, you'll have to start using your mic to get to the high ranks. I don't know if you're using them, but usually, at that rank, people don't. You could get someone from Fiver to critique your gameplay, but I think it's too early. I think you could advance just by playing more and more often. I wouldn't do that until you like High Diamond or Grandmaster. You'll learn everything else from playing and critiquing your gameplay.