Does anyone else struggle with the OP characters?

In games like these, i am one of the people who enjoys trying to get good/decent with every character, but i have noticed that i am really struggling at playing well as the characters that pretty much everyone knows how to play/ the OP characters (cherry cause i suck at aiming with lobbing type attack, string cheese since i am always running out of ammo without getting enough hits and also suck at using her ultimate, and blue slushy who i am getting better at getting kills with, but suck as staying alive). Does anyone have tips to help me get better?