I felt exactly the same way when I started AST as I had also just leveled WHM in SB after maining SCH in HW so both major in the personal damage department.
I do think Tsuki/Baka Games is a great reference point.
For me personally I had to focus really hard on prioritizing my cards over my own personal DPS. A lot of the time on AST I don't even see the chunk that my Malefic is taking out of the enemy health bar which is frustrating coming from WHM where I was always doing more than at least the tank.
Funnily enough playing BRD has helped me on AST. The mentality of focusing on the needs of others and making their own damage potential increase is a nice feeling now. I still much prefer destroying things myself on WHM but there is clearly a time and place to play AST.
