I’ll tell you based on my knowledge and from a PvP prospective mostly, as I only level with a thief at this moment.
I feel like thieves are where they belong, having lots of utility and can do a big burst if you get your opener straight. They lack resiliance although if you go with the sword/pistol build you’ll get more utility and vitality that you’ll ever need – for a decent amount of damage reduction.
From what I’ve experienced with the Warrior class, it has alot of variety and is very flexible for different playstyles. To me they are a * to fight against since they have alot of vitality and can tear you up in a matter of seconds along with disabling you if they chain it right. I didn’t really get to play as one enough to give you my full personal opinion about them but warriors are looking very good for an aggresive type of player.
Engineering is definitly a proffesion you should look into more if you say you’re looking for a slow pace playstyle. It does require alot of focus and experience to do things right with an engineer but it’s definitly rewarding! Although you’ve mentioned you don’t like supporting and thats what engineers do best in my opinion.
PvE wise I think thieves are the sneaky assasins that need to abuse their stealth in order to maximize their potential, Warriors should be in the frontlines and spank the mobs hard and Engineers are more supportive in a way, dealing less damage compared to most proffesions but having the utilty to boost other’s damage.
Wish you best of luck with your choices :).
And remember, you can always re-roll.
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