I'm not sure of this but your lack of weather helm might be a result of the position of your forestay. You might be experiencing lee helm.
I have set the forestay longer by an inch than that recommended by the comprehensive guideline from North for the boat. I did it initially to help pointing and it worked for that somewhat but I feel it could use some more. We don't have lee helm for sure but there is little if any weather helm. You could set the tiller handle down on your leg and it won't try to move till something changes.
All it takes is ONE person on the boat that understands what he's doing - like a manager. Without a manager you have chaos.
We have a good group of Guys with three of us having a fair amount of experience. The challenge, and I think it is a good one is that we have 3 people thinking like managers. As Skipper I make the final calls but I do like people to express their opinions and to try things so it all works out in the end but takes some time to get to 95% or wherever we will get. We have good polars, a good trim guide, and good sails so we are really close.
Finally, I bought an Vakaros Atlas which tracks your race and gives you an electronic track you can analyze.
Thanks, Dan