True heavyweights. You are surely using all the bow has to offer. A quiet bow is much more important than a "fast" bow as you already know.
A few years back I used a similar set up, and it did work. My shots were very quiet, but I was concerned about the longer shots (18-25 yds) when it was gonna count, so I was passing when I wouldn`t have the year before when I was using a different set up.
The next year I began trimming arrow weight. I ended up at about 610 grains @ 63 lbs. Without increasing bow noise much, I increased arrow speed
until I felt comfortable that a relaxed deer wouldn`t be scooting by the time my broadhead got there. My bow creates a pleasant thump, and my arrows are almost always in the ground for inspection after a hit.
Compound shooters are ALWAYS shocked at how heavy my arrows are. I have never been more confident with a set up as what I have now. It is a personal preference. Close broadside hits to the ribs and your arrows will always be easy to find,
thats for sure.