I can try filming a close up slow-mo of me shooting with the 67 flex
Do you think I might be better suited for a 60 flex? The half your weight rule would suggest 67 (135lbs), but it seems a lot of players drop below that. Perhaps I'm having difficulty flexing the stick enough
The half the body weight rule of thumb IMHO gives you the high end of what you should be using. From the bits of info I've gleaned over the years, I don't think there are too many NHL players that go above 50%. In fact, the trend right now is for players to go down.
I saw a video of a a Warrior stick rep saying that the flex range in the NHL used to be between 85-100, but now, 85 tends to be the high point.
Again, it's about preference. But a general rule of thumb test you can do is to see how difficult it is for you to flex the stick one inch, without dropping all your weight onto it. Ideally, it should take almost no effort at all.
I'm 5'5 175. Because of my height and because I use a short stick, I don't have as much leverage to flex a stick, so I use a 50 flex stick for ice.
You're tall, so that can give you an advantage in terms of getting a stick to flex, so a higher flex stick may not be out of the question. If you film yourself shooting, you should be able to see how much you flex the stick. You should be able to see the stick bowing out.
If you can, maybe see if you can find someone with a lighter flex stick that you can take a few shots with and see if there's a difference in velocity.