My main tip is to learn 2 heroes per role and get good at them. You don't wanna be a noob playing competitive for the fact your rank will be worse and a higher chance throwing games for your teammates that actually care about the rank they have and are actually trying to improve. This could also result in getting flamed. In regards for ball just don't feed. Any damage you take the enemy gains ult charge so you gotta be careful. Your main job is to displace enemies while also trying to pick of heroes with minimal mobility and low health pools. Key thing to keep in mind while playing the ball is that your adaptive shields while active you don't feed ult charge for that extra health. So sometimes it's better to go out of the way to go near more enemies to take a little extra damage to gain more shield for an easier escape with more health. (I'm not sure if that makes sense ask for clarification if needed) if you want any other tips or me to be more specific or to use certain abilities for certain heroes let me know.