Paul,
Is there any way to get some pics of the 2 boats that you can tell the angle of attack of your hulls.
The most common problem I witness with people who complain that they can not go to weather, especially as the wind picks up is that they are pinching. With a little more wind you may feel powered up, but if you are not driving off using your leverage and generating that extra power and hence lift you may be loosing a lot of gound.
Just an observation worth looking at.
Matt