The buff are good enough. Some are usefull in dungeon, some in raid, some combo are quit helpfull in solo quest.
Do you use Cleric stance ? Do you optimize your use of Luminiferous Aether and Lightspeed in order to spam Gravity in a group of ennemies after you put your dot on them ? Keep a Spear card in order to use it when it's time to use these 2 abilities.

Personally, one thing I think will fix AST for good is to lower card draw cooldown to 15 seconds.
15 or 20 seconds wouldn't be op i think. 30 seconde is a bit too much when you don't draw the good cards.
And... it's too bad that it's not possible to double up different buff on th same target. I'd like to be able to in order to create a good burst on someone who just used his offensive abilities. Like Balance(royal road) + Arrow (one that i kept in my deck and the other that i just drew)