Honestly, if you are not that experienced at ADC but want to learn it, Ashe or Jinx are what i would recommend.
Both of them rely on the basic ADC principles (DPS, positioning,kiting ) and have a global snipe, which is probably as basic yet impactful as an ADC Ult can get.
Both of them have some sort of "Noob Assisstance" for those basic principles since actually mastering them takes a hell of a lot of time. Ashe is a kiting queen and Jinx`s range buff on the rockets and their Aoe DMG makes positioning in fights easier.
Now if you want to keep that mid lane playstyle of ability reliance then Jhin,Lucian and Varus ( most will say Varus is really weak, but if you play him well then jesus can he get some work done, especially with a tank meta coming up) are a good choice, though i personally do not like people that play ADC and rely on that kinda gameplay alone ( i dunno i just really like the way ADC has originally been ) .
Both Styles can work, if you get into lategame as Jinx without beeing taken out of the game before, then you are a runnung riot, but a mehcanically good lucian will destroy the lanephase and midgame.
Now, all of that is only the opinion of a gold player, so anyone actually good at the game is free to correct me.
EDIT:
If you are used to playing mobile champs and do not want to give up the slipperiness then lucian or ez are probably the way to go ( Jinx passive is sufficient for that as well) .