Take out Kanan first so you don’t have to deal with all the counterattacks. Ezra’s next because he’ll attack twice and can call someone to assist. Don’t use AoE until Kanan is gone, then use it with impunity and extreme prejudice!
Gear and mods are very important. Improve those as often as you can.
Lastly—be patient and perseverant. You can’t change your leaderboard, but neither can anyone else. Nor will anyone be added to your board once it fills up. Practically, this means if you just keep playing, eventually you will overtake all the inactive players on your board and get better rewards through simple attrition.
