There are many factors in this, and not just one simple answer. For the most part though its the frame length, width, and heights, IE pegs to the seat, and the seat to the bars. Then there is motor placement. As stated above where the a-arms meet the frame, also the angle of how the spindles are roated. The swing arm into the frame have alot ot do with the front and back power placement. The banshee is a long heavy machine, when you put it up to the 250r, but then you have the power to weight ratio of the twin vs. a single.
Other factors to concider are how you have your set-up most track quad are built for jsut that, top notch suspension, anti-vibe just about everything, and the weights of every part is kept low.
To reduce fatigue and arm pump, probably a +1 stem with anti-vibe, or maybe the fast flexx bars. Wider a-arms and a good set of say zero pre-load shocks, +1 up on the foot pegs. You might also want to think anout a 2-1 carb set-up less to push with your thumb or a twist throttle.