I'm in the same boat with ya.
I just bought a new bow on Friday a Mathews Switchback,this will be my elk/deer/antelope bow.
I will be hunting mainly elk.
I have it set @ 70 lbs shooting Gold Tip 55/75 pro xt arrows and 100 gr Steel Force broad head.

You should look at having a arrow weight of 400 gr or more for elk.Mine are pretty light right close to 400 gr.With a 28 in draw and good BH it will take elk.