I wish i saw this thread sooner.
First thing... the assassin is probably the hardest plane to setup and fly...EVER. The CG must be within a mm or 2..and if not, it WONT FLY. Looking at the motor esc combo you have on it, it would be hard pressed to get that thing to balance...and if you did.. the amount of power it would create on take off would turn fatal because the plane needs some speed to keep it flying in the correct direction. Think of a rocket on a failed launch where it flips end over end
The next thing is your covering. If you can find my assassin posts on rcg..or maybe here, I used the same CF vinyl...at first. It just weights too much. remove it. you need the plane to be as light as possible, more so because you have the motor that weights 35g+ more than what I was flying... then your battery being 2200, which is double then the 1300 i was using. then your lead, which is a HUUUGE amount to add.
Either retire the plane and do what everyone has said before.....BUY A SWIFT II
Replace motor with lighter motor.
replace esc with no more than a 30a (you will need a 14-18A motor at most)
replace 2200 with 1300 MAX (rhino 850 is better)
move all componets around to balance without adding any weight.
once done... add a HUGE amount of reflex (up elevator) to the wing.
Side arm launch with power, while a few running steps helps a huge amount to get some air over the wing to help with MASSIVE torque roll with this piece of shit horribly designed plane.