I will now ramble a bit about the weaknesses of champions that are strong at every point of the game

I don't know of too many that I can say but the most prominent thing that comes to mind is miss fortune. powerful q crit bullying in lane if your carry has no clue about positioning (which let's face it, they don't.) massive ad scalings and aoe feeding into a decent midgame and a powerful lategame with her ult. I also know she has defined weaknesses such as "to do all of her dps she requires a frontline and to stand stock still and hope to god the enemy team does the same and they didn't bring a braum/yasuo" but

TL;DR my question is, is riot okay with a champion that's never bad at any stage of the game and excels in several aspects and how do they usually go about designing these champions' power curves? I've heard mf called a lane bully and I've heard her called a hypercarry, and while she's not exactly the hellions lovechild of caitlynn and vayne as some people would have me believe, she certainly isn't too far shy of their power. I've played kalista and stomped in lane only to be deleted in a 1v1 with a mf that was 2 items behind my 3 item streak. she literally had a shiv and a bf sword and took the stuffing out of a then pre-crushing-nerfs kalista.