im not telling you to main those roles unless if you don't care about fun. In soloq, pick offs and split pushers are stronger then other strategies because you don't need a coordinated team to do it, and you will exploit the bad players and tilt the enemy team before the important fights start

1º Jungler: you have impact all 3 lanes directly or indirectly and you are the most important member when doing neutral objectives because of the smite. Notable Junglers: Nunu is good overall and easy to play, Kha'zix, elise and evelynn are amazing at pick offs

2º Bot lane: you can destroy the game easily when rotate after geting the t1 especially when the both are duo. Its hard to tell if adc or sup is the most impactfull because the sup its more important on the lane phase, but the adc is more important in teamfighting. notable adc: samira is strong at teamfighting and lane phase, everyone want to focus the adc this makes tristana a nice option she is the adc with most escapes. notable sup: Thresh have a strong pick off, can save dumb teammates with W, Leona is a CC machine and very tank, nautilus have a stronger pick off then leona but is a bit more squishy

3º Mid: you can impact the intire map because you are in the middle the problem is that everyone can gank. Mid its worse then bot lane, because its better have a fed bot lane then a fed mid laner. notable mid laners: Qiyanna have CC, akali W, pick off, burst, and a strong ultimate, Fizz have one of the strongest lane phases in mid and a strong pick off with R, LeBlanc is very versatile and very hard to kill

4º Top: you do nothing in the game without tp(imagine if you bring ignite), unless if you have a skill of global presence. notable top laners: Fiora is the best split pusher and 1v1 champion, quinn have global presence, sett and voli have a strong 1v1 potential, mordekaiser is the best AP top laner because of his versatile ultimate