Melee fighters are powerful, full agree. Mages are much more powerful in this game than they are in 5e. You may miss, but you can afford to risk more of your spell slots in one encounter, since you can get them all back at any time outside of combat. Not to mention the ways you can increase your chance to hit, like high ground. Even if your chance to hit still isn't to your liking, there's always Ol' Faithful, aka magic missile. It's a nice way to guarantee some damage is done. If you have an enemy at low health, and you don't want to waste the rest of your party's actions on such a weakened enemy, magic missile will just delete it.
Oh yeah, MM is old faithful in this game, the majority of the other spells are trash atm, hopefully they will tweak them by launch.