Rounding Out My Champion Pool for Ranked

I have been practicing about 1.5 seasons now, so I am now getting ready to try climbing ranked. I took a dip in Season 7, placing Silver 1 after placements. I want to reach Gold just to prove to my bronzie friends that I am better than the average player. I was a Pantheon main, but after seeing the limits of click to target skills I switched to Shen and have been happier with more consistent games regardless of match ups (since Shen scales better, farms under turret and unfavorable match ups better).

I need a secondary top pick though (Shen is getting banned or picked more than I expected), one that is a solid pick but can also cover some of Shen`s harder match ups (like Illaoi or Yorick). I am thinking Cho Gath or Sion, but want some secondary opinion.

Also wondering if I should pick ADC or Support secondary. I am a solid Jhin, Caitlyn, and Ashe player (all of which suck right now unfortunately), but I prefer to play make, as I am a decent mage support as well as Thresh (by extension Blitzcrank too, but I like to have more peel options for my carries). I am afraid to put support secondary because I fear getting placed support too often though my primary is top (more confident in my support play than my ADC play though, especially in current meta...then again, I have had much more ADC practice lately than Support).

Thanks in advance for your input.