I must say

[Aldwin]

Actually as long as you have an enemy targeted, your weapon is out and you're able to select actions off your action bar you should auto-attack. A little sword icon pops up near the enemy name/health thing when you're able to auto-attack and your character will do so automatically when within range.

What I meant here was, from passive mode to attack, it "feels" to me like there is an extra action that is not needed.

Example being, you target an enemy, you confirm the target (<- this I think should put you in combat mode and start autoattack, by confirming the selection) then you hit your key for combat mode (<- the not needed action IMO). That's 3 keys to start auto attacking, assuming you didn't use an ability.