My opinion, is follow the Dr Ed Ashby Studies on arrow building based on lethality on game animals. You can find the information you seek at
https://www.ashbybowhunting.org/ under reports. After 60 plus years of bowhunting I have tried almost every combination of arrow setup (light, moderate and heavy). I've tried tons of broadhead combinations and ignored the Ashby Studies because rumor was it didn't matter because I was a modern compound shooter. The Ashby Foundation continues to study arrow lethality which includes trajectory, momentum, energy, etc. Yes I gave up some trajectory and arrow speed, but I increased my harvest rate and overall bowhunter satisfaction. PM if you have additional questions.
Good luck.
We've gone back and forth on this one before. To each their own and I have much, much more limited experience but my objection is that Ashby Fdn
is not studying lethality and definitely not trajectory. They say use "the heaviest arrow with a trajectory YOU find acceptable" then some of them are constantly saying that the downsides of trajectory and time in flight aren't factors you should weigh into your setup and it's essentially irrelevant. Which is as in denial as the guy who shoots a 375 grain arrow with a 3 blade 2" cut mechanical at 305 fps and says it's the best setup for everyone. Physics is real, it cuts both ways and everyone's needs are different.
Normal weight arrows like
@Mighty Mouse pointed out balance out the factors really well. If you're concerned about penetration shoot a well designed extremely sharp cut on contact broadhead. That's where you'll get the best bang for your buck even according to the Ashby Fdn and the downsides are next to none. Say a Iron Will SB 100 grain head on a durable 5mm shaft, upgraded components, 15%ish FOC and a total arrow weight in the 400-500 grains going 265-295 fps depending on the archers setup. There's extremely few downsides to that setup.
Ashby Fdn are studying penetration - on dead game exclusively. Which is valuable but there's controlled variables in their testing. Dead animals have a known range. Dead animals don't move. You have all the time in the world to get your form and there's zero pressure. You've got a perfectly clear line of sight to the dead target. You got all day to pick your shot. They perform the same testing procedures and get the same results, which isn't surprising. It's relevant but it's no where near the gold standard it's presented as. The reality is that a heavy arrow could actually make you hit bone you could have avoided with the lighter arrow due to added range error. Or it could put you in the guts that the normal arrow hit liver due to giving the animal more time to move. Etc.
Again, my point is that it's valuable information but it's extremely narrow testing. They have not done any studies that show that their setups have any more lethality across hunters. Meaning studies across hunters platforms as to who has the highest harvest rate. Some studies that have done this actually show mechanicals are better. I'm not saying they are - it just needs repeated. Watching some of the popular guys like THP who shoot these heavy setups, I'm not at all taking away with the conclusion that their setups are more lethal. They call the dogs all the time for shots too far back, high, low, etc.
I've put together polls and asked the question - when shooting mechanicals how often do you get a pass through? The vast majority of respondents said they most often or always get a pass through. So while these "fail" videos are great - if a 2" cut energy sucking mechanical most often or always gets a pass through... then why are we talking about penetration? There's not this epidemic of penetration issues like is presented by the Ashby Fdn. Heck, most guys I know still shoot Rage for whitetails and LOVE them. I still think the design is subpar but hey there's a lot of guys who swear by them.
I've tested enough broadheads and arrow setups now to be 100% convinced that heavy arrows and unvented long broadheads are not for me whatsoever. I'm happy your having success with them but I couldn't even get to the field with them as my confidence was so low. My accuracy in hunting conditions just isn't there and no amount of tuning gets me to where I want to be. Forgiveness is what I'm looking for.