Need to expand my champion pool away from ranged mages.

When I originally started playing League 2 years ago I started with ranged ap mages midlane since I didn't want to feed too much when playing with my friends. I started with , moved onto , and then picked up as a support/mid. For top I use and for JG I use . Those are basically the champs I use for 80-90% of games

A lot of them are skillshot reliant and I'd say I'm not the best at hitting those. Highest I ever got to was Silver 2 in ranked and now I'm trying to get out of bronze in the new season. Playing with my friends in a queue I can usually just cc and help them since they are gold level and get carried. Playing with them taught me better game mechanics than the level I am at currently(Bronze 3). With ranked on my own though, I dont feel like these champs can get me to carry a lot of the time. If I don't start well, I become irrelevant or if I do start well, I drop off after laning phase when I can't keep up on CS.

What champs can I start playing that are more involved in mid/late game with carry potential? Especially for midlane/support?

Also any tips to play the champs I do play already to improve their viability?