I would say MF is the worst out of the bunch. She has no real niche anymore that isn't outdone by almost any other adc. I guess you could say her ultimate is still a defining feature, but it is so easily stopped now by walls from
and
that she just doesn't really have a place anymore. Some people will say "but AP MF" but this doesn't matter to this argument because she is supposed to be an ADC, not an APC.
Sivir has great map movement and decent poke.
Varus has great poke and an initiation, something a lot of ADC's lack.
Ashe is a late game monster with initiation and lots of zone control from W.
Quinn can win almost all ADC matchups if she lands her Q, but will lose almost all other if she misses. She does, though, work really well in top lane as a counter to melee bruisers, so while I feel she could use some love, she has at least something going for her.
Corki and Graves are fine, just out shined late game.
Draven is the main reason I feel MF is dead. He basically became MF 2.0 or 3.0 before he received his much needed nerfs. MF was always the premier lane bully, then draven comes and takes her place. Then a guy named Lucian comes too and he just kind of removed any chance that she would be seeing the light of day again.