Honestly you are not going to get a fantastic vertical performance out of a hover on a 40 size plane with a 46 in it... The twist 40 v2 has a weight (obtained from horizonhobby.com) of 5-6 lbs... if you want to get into 3d with it i would suggest getting a slightly bigger motor such as an os 55ax... it has the same mounting dimensions as the 46 and its inexpensive but it will allow you to spin a larger prop increasing airflow over your control surfaces... It will also make hovering easier. When you are hovering you are in a stalled position and are controlling the plane from the movement of air being pushed by the propeller over your control surfaces... a larger motor swinging a larger prop increases prop wash therefore giving you more control in a hover.


Regarding cg...I always spend some time messing with it until the plane flies upright and inverted without any elevator input (or very little). That seems to be a pretty good starting point I think. another point is that you should also laterally balance the plane...