Kog'Maw is actually one of the best hyper carries in the game and is one of the best late game champs in the ADC role, so i wouldn't put him in with Sona. Aphelios isn't the best either since riot nerfed his damage and early game too much, I would say a solid B tier for him.
I mean I personally consider Kog'Maw a super bad ADC however current winrates are saying very clearly that he is actually much better then he seems at the first glance. I agree with you that he should be moved up by a tier or more as his winrates are above 50% at almost all ranks and in high Master and Grandmaster ELO his winrate is actually almost 55%!!!
Thanks for understanding. I know this is opinion based as well and I hate going by win rates, just do whatever you think is right. Thanks for the quick response!
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