Role / champs for solo que - Advice Wanted from high elo players that have Smurfs

looking for a main role, and then a main champ in that role...

I usually play mid lux and it goes well if the team is half decent but sometimes even if i get fed, I feel like I don't have a huge impact on the game if my team isn't doing so well. I thought about playing ADC again, or maybe even learning jungle. Would like some smurfs that climb easily in low elo to post main / secondary and 2 champs in each for me to main, Thanks a lot in advance