Am i wrong for thinking this way?

I am a Sion main, currently sitting at 175-180k points with him so far. I really love everything about him and i thought that Riot did a fantastic job on his rework. I pretty much know everything about him, all of the cool tricks and what not, after all, i do main him right? So long story short, i decide that after having 100k+ points in him, i'd be suitable for ranked games. After nearly getting out of Silver V with him and losing my series i wondered, is the only efficient way of climbing elo to play champions that have minimal counterplay? Sion has so much counterplay in his kit, he is not overpowered and is in a healthy spot as of right now. But ive been having such an odd feeling lately. Almost as if i regret maining someone like Sion rather than someone like Vayne, Shyvana, Fiora, Gangplank, Darius, Zed ect. I perform well in ranked games but for some odd reason i've been having this feeling that in ranked games, you can't play champions that you genuinely like playing. Someone said that i have to abuse overpowered low-counterplay champions (which sion is not) in order to efficiently climb. I don't know... Should i even bother playing him anymore or should i pick up someone else?