daily login rewards
daily missions/quests, weekly missions/quests
make everything purchasable with ingame currency as an alternative to fast tracking with real money
way more skins
unlockable animations and effects to mix up our abilities visually
make all the characters unlockable through ingame currency, real money or challenges
put a lot more “sizzle” into major dopamine events, celebration sounds, dazzling displays, a clap on the back. This makes them WAY more addicting
give bonuses to rewards for playing with friends
add in a compelling recruit-a-friend system
allow players to immediately vote for surrender if they lost players, or start filling everything with bots
go f2p after you make things more addictive, a la evolve
add animated badges and statements that you can unlock
pull back the camera to 3rd person so players can get addicted to how awesome their character looks and acts
add lots of rewards for simply participating, not just winning