quanta denial decks have to get going really fast, so it probably would have been a lot more successfull with 2x mark. (a turn 2 devourer changes so many things)
Also, if you are designing fractalbased decks you are pretty much fucked if the opponent plays Ray of Light (it's the AIs fault).
Fractal also tends to clog your hand (thats the Oracles fault).
Dimshield doesnt really fulfill a role in this deck, so just scrap it next time.
Also, it's only natural that an arenadeck with only 42 points to spent has a harder time to get wins than one with 59 points.