Best Mid Laner to Main?

Ok, I want to be a mid laner. I will be duo que for 90% of my ranked games (with coms). He will play top. I am looking for a main. This champion would Ideally have decent scaling, good teamfighting, and good 1v1 potential. I was thinking Sylas, Qiyana, Azir, Yasuo, Vladimir, Irelia, or Rumble. Skill Cap doesn't matter! Thanks for any responses and PLEASE DO THE POLL, LelsersLasers TLDR: Want a Main to Master/One-trick, do poll.
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