All 3 mage specs are very enjoyable i prefer arcane over fire only cuz i like the look of the spells more and arcane missiles are my fav looking spell in the game arcane also does real nice dmg tho its the only dps spec in the game that you need to watch your mana so thats imo the only downside but the last time i checked fire was top dmg of the 3 specs i play fire more then frost only cuz the instant pyroblasts is cooler looking then frosts big button proc spell but then again frost is fun when you get a instant cast big dmg flurry and then 2 instant cast big dmg ice lances

Looks like for mythic+ season 4 its fire>frost>arcane for dmg but frost and arcane are still both b tier but i also dont play meta since its usually not fun anyways