You should take the conditions of your preferred sailing location into consideration. In your profile you are saying "NORWAY west coast" That's the coastline to the open ocean with a lot of rocks just below the waterline, right? The so called "updated" newer plattforms with flat bottom create a lot of lift and lay high on the water compared to the more rounded shape like Tiger and Hawk. So low aspect Daggers, rounded bottom etc. may show some advantage on these conditions. The Tiger is a very robust boat and still competitive in these conditions which are different from lake water racing which is mainly flat water. My crew and i are big boys too. we are aroung 100lbs overweighted compared to average F18 crew weight. This is far more impacting your performance than boat design. Just my 0.02
cheers from germany