RE: Point weight?
The Way I look at it is, The bigger the animal Am going for the bigger the broadhead, For elk I use Grizzley's 150GR.
For southern deer 100 to 125 Gr.; Penetration with broadheads and Trad bows is going to depend on the distance and how sharp your blades are.
I spend lots of time just getting my broadheads really really sharp, until I can cut paper with them as if were a scalpel I don't stop tuning them.
And I do go over them everytime I go out hunting.
My favorite bow is a #50 self made 72" Hickory and bamboo, which has taken a 1400 buffalo at 14 yrds, one 750lB spike elk, and many many wildboars ,weighing in excess of 250 lBS, penetration is just that , sharpness.