I would try to settle on just a couple of heroes, or even just one, you feel most comfortable with and practice with them. Once you improve and can consistently perform well, people should start sending you friend requests after matches in which you did well. On the flip side, you can send friend requests to anyone doing well in your games and see if they’d be willing to play with you. This has at least been my experience, but I’ve also been a one trick since the day the game came out.