Picking top-tier champions vs your main(s)

Seems a lot of people pick top tier champions in order to win games these days, and it's totally understandable.

I mean are freaken good junglers whom have game changing kits / plays. Supports like have the best kits for peeling / protecting your allies.

However, it begs the question ... does someone do better when they pick a strong champion or stick with their main? Granted, I know mains are hurting really badly and deserve some loving from Riot, but I mean ... shouldn't you just stick with your main(s) if you're playing ranked? I have had some great games picking but i've got to Platinum thanks to whom are 'good' but not the top tier supports. Even before were a thing, I was climbing more games with greater success using my mains than trying to climb with the best supports. This isn't to say you should stick with your mains, but I wanted to know your guy's opinion on this.

Sadly, as of lately because of how the game has changed ... i'm starting to spam in rank because she's got the kit to make amazing plays and save allies, when my actual main can only go all in and get picks, not much else, even items like can only do so much when champs like can do that and more with their kits, giving ADC's way more resistance / security / sustain / protection than what Leona could ever do. This makes me sad because as much as I WANT to climb with my main, I am resorting to the popular picks. Again, how do you guys feel about top tier picks vs your main(s)?