Well, I would recommend to have a look at these cool 8 person 4 season tents for camping as an option. This resource will help you make the right choice and spend great holidays outside. Simply check out the list of features and pick up your best camping shelter.
Most really good tents are at the most 3-season tents. To find a good 4-season tent you are going to spend some $$$. At best, find a really good 3-season tent, and for the cold weather, use the rain fly, on the outside. Then use a thick wool blanket to make a carpeted floor on the inside. Then add sleeping pads for each sleeping bag, or use a cot, to keep you insulated from the cold of the floor.