You're going to find many different opinions on this, none of which are necessarily wrong. When I was younger and hunted a lot more than I do now, 125 grain broadheads seemed to be the norm, and nobody worried about it that much. Now, due in large part to studies of penetration done by Dr. Ashby and confirmed by the subsequent experience of others, people are using more weight up front to get better penetration. Some of this can be obtained without increasing the overall arrow weight by combining a heavier point with a lighter shaft. For example, my current hunting arrow has 220 grains up front combined broadhead and insert, on a Victory VAP shaft. This is actually lighter weight overall than the arrow I was using 20 years ago with a 125 grain broadhead. So all things being equal, I should get the same or flatter trajectory today with my 220 grains up front than I used to get with approx 140 grains up front. (Of course, all things are not equal, starting with my loss of strength over the last 20 years, but it's nice to know that improvements in equipment can help offset at least a part of that). My gpp for my hunting setup is just under 9 gpp.
I shoot a totally different setup for 3D tournaments, which optimizes my ability to shoot 100 arrows in a day as opposed to maybe a dozen in a day hunting, including practice shots. Point weight is not important when shooting 3D, other than wanting to exceed 10% FOC for accuracy purposes, which I can get with 90 grains up front combined point and insert weight. My gpp hovers around 8 gpp for my 3D setup.