you can get by just fine spamming arcane explosion and barrage on multitarget and arcane blast spam on single target
A six year old could play the game with these three abilities and that’s all
He didn’t ask for minmax he asked for easy to play. Arcane is the easiest spec to play in the game for a new player, hands down.
I highly disagree. On ANY spec you can “get by” just pressing your 3 highest damage abilities, are you kidding me?
Holy Paladin.
I disagree with WW Monk. Unless you want to gimp yourself most of their good talents are active talents and add quite a few buttons to the rotation.
my WW has more buttons to press than any other class I play. Kinda reminds me of Fury Warrior, except you really need to push them in order on WW to unlock other abilities.
Won’t say WW is HARD, but it is very active compared to alot of other specs I play.
If you want a slower pace spec, go MM Hunter…Its pretty slow pace and is solid
I find MM to be easier than BM, cause MM doesn’t have to keep up with barbed shot stacks…Just figure out how trick shots work and hit your night fae ability on big stacks and your gonna top meters 
I can’t upvote this enough.
Rogue. Rogues have 2 buttons.
Have him go with something like ret pally or frost dk imo. Not very complicated rotations, heavy armor and straightforward self heals.
He should really pick what appeals to him though. Most likely to do well with something fun for him.
Death knight specs are very easy. You don’t have to worry about team. Just face smash and zug.
Having played a lot of specs over a lot of years, I can say from my personal experience, BM hunter is one I find easier to play. I find myself watching the “game” more whereas as with other classes I’m watching the action bar-waiting for cool downs, or procs from abilities/talents.
You also have the advantage of having a pet(or two!) to make open world elites easier to take.
I love my BM hunter.
BM hunter. It’s absolutely a braindead spec right now.
I would say Arcane Mage. The rotation is really, really straight forward, since the difficulty comes from mana management, not how many keybinds you press.
I have 3 hunters. BM is a lot more simple than even MM right now. It’s the most braindead spec I’ve ever seen Blizzard put out.
I can tell you it isn’t Warlock or monk
We have enough casuals in this game. Have your friend go play Club Penguin.
I’m kidding.
Your friend should just keep playing Fortnite.
casual gamer here and a low level player (meaning I really do stink lol )
BM hunter is the only one i"m confident in my skills. it’s easy rotation especially now with the add on which literally highlights the buttons i should push lol
having said that… I do also enjoy Ret Pally and Frost Mage (though this expac seems hard on her)
hope they have some fun!
Seriously Beastmaster Hunter or Frost Mage. They get a pet so the casual player can bond with their npc friend that helps them a lot!
Not DH or Ret?
I am assuming you are looking at melee damage dealers, in that case I would say Frost DK is the easiest to play.
I’m going to vote for destro warlock and beast master hunter. Not only do you get a simple rotation, you get a pet to tank for you.
Hunter might be a bit easier to play since all of the spells are insta-cast, they have superior movement compared to any other ranged class.