Arena is now streamlined, surprisingly responsive, and most crucially, begins with a short tutorial showing newcomers and returning players how Magic works in 2018
And look, I know there are a lot of discussions around painting all these cards with the same brush despite being banned for different reasons, however (and without derailing the conversation to talk about the banned cards) there were better ways that WotC could have handled all this.
We know how good landfall triggers are already at the kitchen table right
It wasn't flashy, but extremely healthy for the format
Regular Creatures, Sorceries, Enchantments, and more can only be played during their owners turn, but Instants can be cast whenever their owner chooses
Getting both an extra combat and a stat boost stacked on top of Treasure token generation lets this do a lot of effects for a combined seven mana