Dont forget that the champions that are banned are always changing and as you go up in the rankings they tend to change as well. I recently managed to move up from silver 5 to plat 5 and I can tell you the most commonly banned champions from each league.
Silver:
Blitzcrank - he can really be annoying in lane and his pulls can mean certain death if landed.
Amumu - His ult can become really annoying and can be seen as op in teamfights
Nasus - He is always op late game, wether you shut him down or not
Gold:
Riven: She can become a real problem in lane and is one of the best champions for carying if played correctly
Fizz: Similar to riven in the idea that he can carry if he is fed enough
Malphite: his ult can be really annoying and if given the chance to be played with a yasuo, man the combo op
Plat:
Eve: with the changes to vision she can be seen as over-powered
Shyvana: Amazing champion if built correctly
Mundo: His ultimate works extremely well with the changes to masteries
Overall as i moved up i saw people saying that blitz pulls were not a problem as people learn how to dodge them but later become an issue in diamond when people become good at landing them. Similar situation with amumu.
The champions that are easiest to carry with preseason 4 would have to be shyvana, mundo, eve, and definitely nasus.
But if you really want to know what champion to carry with I would say your best :)! Every champion can be good if played with the right person.
