My personal advice is: don’t “main” any hero in Dota. It’s just a poor way to play the game and you’re hindering your own experience. You can learn so much from playing many heroes. It’s okay to have favourite heroes of course, but you should pick those because you like the way they play, feel or look. Picking them based on your winrates is a recipe for disappointment, because that winrate will eventually go down, whether it is by nerfs or just good ol’ statistics.