thanks you for your reply.
my current tent is a Marmot Asgard 3p it weighs nearly 6kg and is a 3 person geodesic. we can just squeese 4 of us in it. it pitches inner first so is often soaking with puddles of water on the floor before we manage to throw the flysheet over. the porch area is a little too small for rucksacs, wet clothing and cooking. because of the shape of the inner, it 'rains' into the inner tent when camping in the winter and the heat from the stove melts the frost on the inside of the fly.
we have been using this tent for 3 years and have outgrown it. the tents i am looking at offer more space, quicker pitching and less weight than my current tent.
remember that we are 4 people, a 6kg tent is only 1.5 kg each (in theory) i don't consider this too much for a tent that will give shelter in all conditions and be totally reliable for many a year.